1 cost u 20-40k

The other one cost u double

actually is there any reason why they dont want do 2 cylinder with higher CC ?

example:

2.0L = 4 cylinder = each cylinder 500C

2.0L = 2 cylinder = each cylinder 1000C

hard to achieve high compression ratio?

all your point i agree, your last point however i dont agree because engine mounting (in fact, any rubber mount/bush) is a wear and tear parts just that they last longer.
just recently i changed my car engine mounting. issues like jerking gear change almost gone already since the engine can grip better now.

so engine mounts dont need to change? engine vibrate more u need stronger engine mounts to withstand the vibration right? tell me which car dont need to change engine mounts after 6-7 years, i want to buy a car that the engine mount last a lifetime also

Explaining them requires a Ph.D but Sandquist briefly said the use of counterweighted crankshafts, dual mass flywheel with centrifugal pendulum absorber damper, single balancing shaft, low noise timing belt, high stiffness oil pan, asymmetric oil pump impeller, engine compartment and vibration dampener – all hidden away from view, allows the 3-cylinder to run very smoothly.

Yes lifetime, which is 5 years max. Ever heard of lifetime transmission no need to replace transmission oil? LOL

skrg ni nk sembang kereta ke kasut?

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https(colon)//www(dot)wapcar(dot)my/news/are-3cylinder-engines-as-good-as-4cylinder-engines-1832 - Are 3-cylinder engines as good as 4-cylinder engines? - Shaun · Apr 10, 2020
And if you’re able to recall, I’m sure there was a noticeable amount of vibration from the engine. That is one of the characteristics of a 3-cylinder engine – the vibration. It’s a rough feeling and because of that, most of us, myself included, have the perception that 3-cylinder engines are on the bottom-rung.

Yet, they seem to be on the rise with both the Proton X50 and Toyota GR Yaris featuring 3-cylinder engines. Even premium brands like BMW and Volvo are employing 3-cylinder engines in their cars. Why is that?

One of the reasons is cost. With one less cylinder than the conventional 4-cylinder engine, the raw materials required is lesser and when this is calculated at scale, the cost savings becomes significant. ...

The main problem with 3-cylinder engines is the vibration as mentioned earlier, particularly at low rpm. Without getting too much into detail, this is due to the imbalanced nature of 3-cylinder engines that causes them to rock about.

Manufacturers tackle this issue by adding a balancing shaft to counteract the force and a variety of solutions that I’m not able to presently comprehend so I’ll just call it witchcraft. BMW seem to have got it right, their 3-cylinder engine exhibits very little perceivable vibration, perhaps only during startup.

The engine in the Geely Binyue, or what is likely to be Proton X50, isn’t quite as accomplished. The 1.5-litre turbocharged 3-cylinder engine, which is co-developed with Volvo, feels even rougher at start up and has just a bit more vibration than the BMW unit. Though for me it is perfectly acceptable.

There is also the matter of sound. To some, 3-cylinder engines sound rough, especially when revved hard. But personally, I quite like it. One way manufacturers attempt to overcome this is to produce synthetic engine noise in the cabin through the speakers. ....

https://www.carthrottle.com/post/heres-the-...linder-engines/ - Here's The Problem With Three-Cylinder Engines - 3 years ago.
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So, the main reason car-makers reduced from the normal 4-cylinder to 3-cylinder and from >2.0L to 1.5L Turbo is to save manufacturing costs = maximize profits, not to benefit the consumers with better fuel efficiency. In fact, true IRL fuel consumption for the Proton X50 is worse.
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and another person mentioned about dampers and balancing shaft too, dampers are wear and tear too, together wif engine mounts, these will wear out faster if the engine vibrates stronger

and u mentioned that engine mount wear on 3 cyl engine is debatable, but basic science logic, if something vibrates stronger, it will require more damping force to smooth out the vibration and thus will reduce the lifespan of the damper

of course there are cases that those conti cars with 3 potters their engine mount still last as long as those cars with 4 cyl, but to achieve that, the materials used in the mounts are stronger and higher grade and customized, this means those mounts will be much more expensive than a standard mount in a 4 cyl engine

the extra costs of replacing the wear n tear parts will be passed on to the consumers

manufacturers are happy cos the engine is cheaper to manufacture and it pass emission tests, but consumers cry when its time to change those wear and tear parts

cannot be just a spring, if its a spring only the engine will bounce up and down, should be like a shock absorber to absorb the bounce (similar to car suspension struts)

well u are using a 1L turbo 125hp 175nm car to compare, but a more powerful and bigger engine like the one in x50, 175hp 255nm will produce a much stronger vibration, and hence stronger mounts and other workarounds like dampers, balancing shafts etc is needed compared to a lower output 3 cyl engine

but of course need to confirm with proton first how much is the mounts cos now we all also unsure hahhaha

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To me, the misinformation is being disseminated by the car-makers and car-trade news media.
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1) Engine mounts are part of vibration dampers, if you havent realized their function

2) The 5 year figure is the typical age when the infamous lifetime transmission fluid failed. To the car manufacturers, lifetime of a car is 5 years or less.

Such improvements are increasing not only cars’ lifespans, but manufacturer warranties. Three years, 36,000 miles used to be standard, but 10-year, 100,000-mile warranties are becoming the norm.

Well you look at the x50 now, only offer 5 years unlimited mileage. What does that tell you?

You don't know what you are talking about.

Many people wanted more power and turbocharging is a CHEAPER ways to get those extra power. Ever wondered why there are so many turbo charged diesel pickup in Malaysia?