People are really sleeping on nc memories, does all the good things but none of the "I decide how your images are stored and nothing else should touch them" that immich does.
When I checked half a year ago memories (with the nc ecosystem) was still ahead in terms of features (gallery specific), albeit object tagging is rather crap in nc (faces better)
You could also upload directly to the filesystem and then run occ files:scan, or if the storage is mounted as external it just works.
Another method is to set your machines /etc/hosts (or equivalent) to the local IP of the instance (if the device is only on lan you can keep it, otherwise remove it after the large transfer).
Now your rounter should not send traffic to itself away, just loop it internally so it never has to go over your isps connection - so running over lan only helps if your switch is faster than your router..
1. Did you open back port request with these basic patches? If you have orders of magnitude speed improvements it would be aswesome to share!
2. You definitively don't need an entire sysadmin team to run nextcloud, in my work (large organisation) there's three instances running (for different parts/purposes of which only one is run by more than one person, and I run myself both my personal instance and for a nonprofit with ~100 persons, it's really not much work after setup (and other systems are plenty of a lot more complicated systems to set up, trust me)
There is also "memories for nextcloud" which basically matches immich in feature set (was ahead until last month), nextcloud+memories make a very strong replacement for gdrive or dropbox
I use my yubikey on both my android and linux (tumbleweed) with exclusively firefox, I have not found something that does not work.. Maybe you mean non-hardware passkeys built into the os? But one could just use keepassxc or like bitwarden, those work in Firefox and Linux as well
There is Nextcloud which is not only eu-based but open source as well. You choose what parts you run but it competes with most of workspace and office 365 (everything but the arguably obscure stuff*). I use all three (g-workspace, office 365 and nextcloud) and I strongly prefer nextcloud excluding my private preference of open source - even more so from an administrative perspective (fuck the workspace admin pages, they causes me so much trouble)
*except email-server which although easy to add on trough stalwart or external email provider is technically not part of the nextcloud ecosystem (webmail is however)
Not zero indexing is misleading if you are comparing discrete things like GPU performance, not in the case of plotting a timeline graph. Their published stats could be seen as misleading if they only displayed a short and/or a specific timeline (excluding the latest data for example).