Can attest that Folder Sync is excellent. I use it all day (in the background) for two-way sync (notes) and backup of photos videos etc
Though a small PSA on setting up:I once set up a new share on a new phone with two-way sync, and the app decided to sync the (newer) empty directory to the server (i.e. delete everything) instead of pulling the files from the server to the phone.Easy fix: Restore notes from backup (step 0: have backups in the first place), then do an initial 1-way sync from server to phone, then change the sync job to two-way.
Hardest issue would probably be financing, and motivation.
GPUs are expensive, electricity is expensive. All the current major LLMs are huge loss leaders for giant players with deep pockets. A distributed AI service would be by smaller players without the financing nor the motivation to upfront all the cost.
There is "folding@home" where you donate time on your hardware for scientific calculations, but that's quite different from donating time on your hardware to some random unknown stranger to generate AI cat images or summarise a news article.
Lemmy and Mastodon etc have a comparatively modest monetary (and energy/environmental) cost, and the benefit is building communities and bringing people together. For distributed AI the cost ( monetary and energy/environmental) is higher, and the benefit is limited.