I bought my main machine 10 years ago. It was a top-notch i7 with 8GB. Nowadays it's a meh machine that barely can play ducklings.io
I just upgraded reinstalled to Debian10 (from Debian 8) with KDE. I did a fresh install because the upgrade from 6 to 7 and 7 to 8 failed (once lost GUI due to X changing, the other time I lost rights to shutdown, due to KDE errors).
On the one hand, some things now "just work". On the other the software is sluggish (copying large files halts the mouse so you have to guess where the mouse will be in 5 seconds, when the mouse is updated) and swaphungry (and I have a slow drive, so I changed the swappiness "sysctl vm.swappiness=30"). It takes weeks to tweak, but it's starting to feel like the trusty ol' machine I had.
On the plus side, I just move my .icedove and thunderbird converted it successfully to the newer version.
Wine is worse on Debian 10. Much slower and some things (the sims) do not work anymore (but it could be me I installed both wine32 and wine64 and have not tweaked too much yet).