Went through some of the optimizations recommended. Slight improvement, but still over 10 second load times on my #corebootbook laptop.
Took a break from it out of frustration, went to my workstation and decided to check out Nextcloud from there. Loaded in half the time.
What's going on? Had a hunch.
Opened htop on one monitor, loaded the Nextcloud Dashboard in the browser. All four cores of the Xeon processor go up to over 50% until the Dashboard loads.
The slow down is on the client side !!! (or at least some of it)
The javascript clientside is doing so much and requiring enough CPU that it takes my lowly corebootbook more than twice as long to load the Nextcloud app.
Other web pages and web apps are not this slow on that same machine.
I really want to love Nextcloud as I plan on hosting it for some of my clients. More than ten second load times are unacceptable, though. Five seconds might be bearable, but not ideal.