Interesting journey and of course you are not a fool. It's called a hobby and for many men, it is costly. I also have 2nd hobby cars and believe me it is more coslty than this. It is not only the upgradeatitis. It is that you always wonder what could be better and of course ti have fun through these journeys.
These days I was blamed from a friend for my hobby and later he told me he had given 10k for a coffee machine...
I had similar itches like you, till I decided to design me own gear from scratch. More difficult journey than the one you had, I was lucky to be Electrical/Electronics Engineer PhD and maths/electronics was easy. Now I have evrything end game except the !@! speakers...