Trouble is, it was a mid-range budget of say $30-$60 million but you immediately subtract at least $10 million for paying Spiner and Stewart...
Already by 1994 sums of $100 million plus where being spent on movies (True Lies) and even in 1991 $94 million went on Terminator 2.
But Schwarzeneggar was routinely pulling in $15-20 million for those films and the producers/directors were able to still make capable big screen movies. Hell, Shatner/Nimoy were eating up huge chunks of the TOS film budgets with their "favored nations" contracts and Bennett, Meyer and Nimoy were also able to make decent looking big screen films.
Berman just had a too much of a TV mentality on the first three films even hiring TV writers/directors to make them.