well. my previous AMD FX system which is still in use by the kids, was 4/5 years old ish before i upgraded the entire system... and i see myself keeping my current one at least for a further 3-4 years before i think about upgrading to a new platform.
i do however make incremental updates to the hardware i use inside it during that time though. like a better GPU, CPU, maybe more RAM, more/better storage. but then again, i am semi enthusiast and love to tinker/benchmark with such upgrades. Plus it also gives me stuff to blog about.
I think RGB is very subjective. the entire industry has been pushing it more and more recently, but as said in the post, it is a broken side of the industry. for me i just have some RGB fans, motherboard and RAM. just to illuminate my hardware and to match my personality. and it is the same for most other people who wish to show of there hardware too. but that is only a select group of people as everyone else, like yourself want the advantage of a PC without it being a distraction.