Chiming in late to this thread but yeah I also build my own PCs. Have since around 2000. My latest build is around 6 years old now but has been a total champ. Back then it was beast and started to show it's age slightly due to graphic card. I upgraded that about 2 1/2 years ago and it has been given a second career, lol. Though now it just might be getting older where I need a new build.
It had a 970gtx that I swapped out with a 1070ti. It has an i7 processor that I can't recall the generation but it's around 6 years old. 16gb of DDR4 memory and 2 SSD hdds (I know now we got the NVMe these days but my mobo doesn't support them). Windows 10 with zero bloatware or even an aftermarket anti-virus. I stick with Windows Defender paired with Adblock Pro for web browsing. I've been virus free for years and PC runs optimal. I only have a 1080p monitor so it is limited there, but because of that I can still just about crank up any game to the max and it breezes through them. Of course I don't get all the new bells and whistles that come with the new cards such as Ray Tracing, but that's fine. The new build I put forth will come with all the new goodies.
Oh yeah, funny too when you said, any other expensive hobbies besides cars. I WISH I only stuck with PC building in my life, lol. When I was 15 yrs old doing it, I was like, how the hell can I afford a motherboard/graphic card/memory. Nowadays, it's like, the price of all of that is 1 car part. It's actually disgusting, lol. I would totally go back to PC building only.