My mum says we spend around 20k per month to feed 7 people. No car loan, no house loan. Just on daily expenses

Actually not really. Some of us choose to be debt free. Why work for banks when you can let banks work for you?

Actually it's very easy for bank to give out money. My credit card limit was basically 10x my salary. Banks love to give out money. Why do you think they dangle ad like free holiday with personal loan?  They are encouraging people to take up loan, to go for holiday,  buy stuff with borrowed money.

Peace of mind that no one is chasing  you for money is priceless vs having to worry that someone is always after your money every month and having to look over your shoulder.

Again I'm going to ignore all other topics that you have brought up but only focusing on these two things:

* on girls
You are generalising. Yes, most girls do spend more than guys simply because of the society's design itself. Everything that girls do invites questions.
If she spends on personal / skincare = waste of money.
If she doesn't use any = didn't take care of herself.

And simply because so far the most girls you've met are like that (spending on bags, shoes, etc) the same could be said of most guys (car, pc gadgets).
In the end it's all down to financial literacy. The "luxury" could be different items but majority are the same.

* on income
Honestly unless you are from very niche industry which no other company will hire you, I really don't know why you are staying in a company after being stagnant for years. They don't value you. Period.

Even if sacre industry is the case, you can still either change career or get out of Malaysia. Bottom line is do something about your income. It'll give you even higher amplified ROI. You can maintain your frugal lifestyle or current mindset for all you want.

P/S it takes two hands to clap. You haven't met the girls with the quality you like, probably because you don't have the quality they seek either. Associating gf = burden is really a big turn off. Especially if its a guy that complain about income (on paycheck portion) but does absolutely nothing on the income (from paycheck portion)

Low income send govt school by neccessity.

High income send whatever school by CHOICE.

Inflation HITS everyone, it does not AFFECT everyone.

Inflation only hits when you SPEND    that's basically the definition of inflation. 
Yes this point is valid. But it doesnt have to apply to everyone. Li Ka Shing and Warren Buffett don't spend like what they are "worth".

If you earn 50k, and spend 50k - you are a poor man

If you earn 50k and spend 10k - you are a rich man

Money can't be brought to grave, but money should be managed wisely. It's not every month and every year you will be earning 50k. Money management lets you to continue spend 10k forever regardless if you are earning or not.
Btw once again inflation dont affect rich ppl and middle income, it hits them - but they can brush it off like its nothing.

Money is not yours unless you spend it. If you dont spend money then the money have NO VALUE at all.
I love it how everytime people talk about "rich" everyone wants to bring in the billionaries and use them as comparison.

So your definition of rich is Li Ka Shing and Buffett? Then everyone else is poor?

Cause pls understand there is a certain base amount you can spend before more money becomes irrelevant. So pls dont bring in Billionaires into the equation unless you want to bring the discussion to a different level.

Now, going back to spending habits, sure if you earn 50k and spend 10k, you will have more "savings". You will not be "rich". Cause if all you EVER do is spend 10k a month, regardless of how much you save its useless and pointless, you ever will spend 10k a month. How can you be "rich"?

Money in the bank that you NEVER use does not make u rich.

U are right in many ways. But in marketing, sales and business industries, you are required to create a strong profile level to double or triple up your current income. Why? Because until today there are still many ppl looking at the surface only. Just like why ppl buy “Dato” title just to gain confidence of any trust to nego any new businesses. And now you know why all the insurance agent buy BMW and MERC to show. Just to do recruitment and buy client confidence that they are doing well in this industry, so that you dont buy a policy with a agent no longer service you in times come.