First time sync initialization makes Obsidian unresponsive

When I first start Obsidian on Windows, the sync stays in “Initializing…” for a good few minutes, where the UI, shortcuts and nothing seems to work. There are 20K notes in the vault, and I do think it gets proportionally worse with more notes. After Sync is done Obsidian is responsive again.

Can it be fixed that this sync thread / activity is done on a way that it does not freeze the use of Obsidian? It loads blazingly fast, but sync makes it unusable for a good while.

The log goes as follows:

2021-09-13 06:26 - Connecting to server
2021-09-13 06:26 - Server pushed .....
2021-09-13 06:29 - Uploading file ....
2021-09-13 06:29 - Server pushed ....
2021-09-13 06:29 - Upload complete ....
2021-09-13 06:29 - Fully synced

Time between "initializing 06:26 and fully synced 06:29 Obsidian did not work, like opening notes, creating a note, no views changed, everything just “froze”

Sometimes it’s unresponsive for me when I’m not online. (it still tries to talk to the server)
Could someone also look into that? Debug window has no info why it happened.

does it happen in restricted mode?