I've finally found a good setup for me: Obsidian syncing to cloudflare R2. The notes are not encrypted in cloudflare (which I would prefer) - that's next on my list.
Perhaps the low hanging fruits in this era of technology/software landscape have been poached. However, I can find hundreds of problems just in the realm of software architecture and infrastructure management that need to be addressed and improved.
Spend a decade in any industry and you will see the gaps more clearly.