Probably because no one was using that feature so they just removed it. But Linux updates don’t any cause problems. They are open source inspected and tested real good before sent out.
Seriously, just go toggle it off. It will keep running great without the updates, most are unneeded. Then once a month go turn it back on and update it if you like.
Or... Set it to auto and it will just keep everything updated all the time. Or if these are apps they are promoting and you will never get or use you can blacklist them in the update manager and they will not pop up anymore.
Where do I toggle it off or to auto though? I either missed the option, or there wasn’t one in the new update manager? I’d rather update like once every few months or so, but then i suppose the updates woild likely be huge considering how many updates there are in just even a week.