Majority of any browser users are not tech people so making these workaround easier would confuse those users as most of the plugins are not written with mobile aspects into consideration (Even their mobile API is not complete yet).

afaik a lot of extensions aren't fully supported yet. I tried about a dozen different tab managers on FF Nightly, none of them worked. I'm guessing the Tab API or something isn't fully ported yet

Not all of the APIs on mobile are production ready yet, so these options are for developers to try their add-ons.

addons are usually hyper tunnel visioned around desktop users and almost none of their ui's work on mobile the way the developers of those extensions originally intended.

ublock and the other featured apps essentially had to adapt to the mobile firefox way of doing stuff and opening settings in a separate mobile ff tab etc.