This is why getting laws passed, instead of relying on executive orders and the whims of bureaucrats in power at the time, is so crucial.
Compromise. Something that neither of the two major parties seem interested in anymore. It is that, not the allocation of seats to a party in Congress, which is why things haven't gotten done.
Then they whine that democrats are jerks when dems call them anything.
If you are talking about Garland then no they didn't. They just didn't vote for months. They just refused to do their jobs.
So laws would be no less vulnerable than FCC regulations.
Having people who are competent at their job in regulatory positions seems just as important as having Congress do their job for them.