I don't really understand people who complain about Nextcloud being slow - for it's intended use case, it's generally fine. I've run it for ages and never had an issue. It only becomes an issue when you start to abuse its functionality.
For something Nextcloud - reliability, stability and security support/updates matter far more than raw speed. I don't care if my document takes 2 seconds to load if it means not handing my data to the CCP ;).
I've had a homelab for many years. The drive for me to move to full self hosting everything was icloud photos.
Had to reinstall my Mac, and as part of that I wanted to take a full backup of my photo library. Clicked "download originals"... Failed. Tried again, downloaded 2 and failed. Contacted support and was told it would be investigated. 6 weeks later I finally had access to my photos.
I said to my wife "no company should be able to stop us accessing our own stuff, there's going to be changes". Beyond email (as I hate running mail servers), 3 years later I use zero cloud services for data.