wife used iphone for many years, then changed to the latest high end samsung....i forgot which phone.
used it for a couple of years, bising how she missed the iphone.
then when the iphone 13 was launched, straight away order the ip13pm 1tb.
been a happy user since.

one thing i can say about iphone is, its durable and last long.
it doesnt go slow or go "bad" as quickly as android phones.

im not the type who buys a new iphone everytime a new model launched.
i used my iphone 3GS for a few years before using iphone 5 when it was launched, and this iphone 5 used for sooooo long before i got the iphone Xr. then after so many years i changed to iphone 12PM and still using it because it is still very good.

3GS - 4 years
5 - 6 years
Xr - 2 years (but passed to my son and still in use total 6th year being used.)
12PM - 4th year ongoing....

maybe my next change is 16 or 17.

so far no issues. maybe a little lag compared to new. battery health percentage is if course not as good as new. now at 79%.
need to change battery or change phones.
if u compare iphone 15PM and then used 12PM of course will feel a significant lag.

the Xr i passed to my son, i did replaced the batteries 2 years back. of course original batteries at authorised service center.

something interesting to share, just so happened yesterday me and wife both did a speedtest for our 5G.
we did it at the same location at the same time.
im using 12PM, she is using 13PM.

my download speed was around 1250 mbps.
hers was 980 mbps. wonder why.

of course in terms of phone speed (lag etc) her phone is much faster.