I have to admit, I added a couple of lines since 1995. About 10 or so

I changed from .emacs to .emacs.d/init.el when it became possible, because that seems neater. Some years later I decided to see what fancy packages the young folks like, and started using vertico, orderless, marginalia, embark, and consult. I'm still going to reserve judgment on embark and consult, but at least the first three packages are certainly great additions.

if your .emacs has 10 LOC it makes it definitely easy. My .emacs is ±360 LOC.

My point is: the api of of emacs is fairly stable. And your point is?

I have ~80 lines outside the customize variable block added by emacs. Nothing too fancy but there are a few hot keys and functions that I can't live without.