My late DH was just the same. Couldn't get in the garage for old computers, VHS recorders, TVs, electric drills and other tools that no longer worked. Cardboard boxes for above items, old hoovers, wires, plugs, cables. Screws, nails, offcuts of wood. The broken parts of a loo he had repaired. A home beer brewing kit, used once in the 70s. The study was just the same. He also kept sentimental bits and pieces from when we cleared out his parents' house, including furniture I wouldn't give house room too.
I didn't dare touch anything, and and any mention of clearing out and going to the tip was met with a firm refusal.
Every magazine he bought also had to be kept, just in case there was a useful article that he might need one day. The day never came, of course.
However I did manage to reduce the pile of magazines but by bit, and he never noticed. I would remove a few every week from the pile in the living room to the pile in the study. Then if he didn't notice them missing, the pile in the study would gradually disappear into the recycling! He never did notice!
He died two years ago and I am still finding bits. I got a skip last year and cleared the garage, but gave the half dozen old bikes and all his tools to a charity which refurbishes them and sends them out to third world countries. My window cleaner also took quite a lot of things, took them to a car boot sale and gave me a share of the proceeds.
But I'd still much rather he were still with me, and all his rubbish!