We have a lot of people at work with 2015 models - and they are SUPER happy. I have the 2018 model with i7 and I can't really see any difference in performance. I love the display, but mostly I use a 27 inch high DPI external screen along with an Apple magic keyboard.
One thing I strongly dislike about the i7 is how hot it can get with long compiles and such. So I think it's time to upgrade to the M1 Pro or Max.
Got the same life out of mine, although the battery swelled up this year. :-/
Didn't bother to look into the cost of replacement as my initial research indicated that they'd want/need to replace the keyboard and upper chassis as well, so probably a $600+ repair. So I opted for a company laptop instead.
Team 2015 MacBook Pro here. This thing still works so very well and only turns into a pavement grinder when it comes to the fan sound when I play Civ6.
Yep. I have a Mac mini, a 13 inch MBPR an 11 inch Air all from around 2013 and they just dropped off the MacOS update path in the last few months. All are more than adequate for general office work including software dev.