Why is Sync so hard to deal with?

I have read and read and still it makes me wonder why it’s so hard to have a sync solution with Dropbox. So my use case is I have begun to migrate from OneNote to Obsidian on my PC, my Mac, and just barely starting on Linux (since I don’t currently work with a OneNote solution on Linux…hence the migration to Obsidian). However, what I have quickly discovered is that I am out of luck when it comes to my mobile devices (iphone & ipad). Of course I can opt to pay for Obsidian Sync but if I paid for every solution that I use Dropbox to sync for I’d be broke. Not that I mind paying for a good solution but I just can’t justify this or understand why such an open platform won’t allow me to filesystem sync.

Case in point, take a password manager like 1Password that utilizes encrypted vaults, it syncs just fine via Dropbox (and iCloud, and Google, etc., etc.) I’ve been told to just use iCloud but there again, another service that I just don’t need or want. I have way too much in Dropbox to have to migrate to another service, not to mention there are other migration issues at play to do that. Additionally, there are issues with iCloud syncing to PCs, even here with folks trying to do it in Obsidian.

I’ve read a ton of various solutions here as well as other forums and most of which are very janky and not something that I would rely upon for anything other than simple testing. The others just don’t work. I’d love to just forklift all of my data and put it into Obsidian because of so many reasons, but this is becoming a hard sell for me, simply because of cross platform sync and it kills me because it’s not that difficult. Especially considering that we’re dealing with a file dependent app anyway.

I know my use case is highly specific to Dropbox but the similarities are there across different services.