The funny thing is we had a cruise out of Miami where everything tasted like it was previously frozen, bad, bland, etc. Everyone we talked to said the same thing. We then had a different cruise out of New Orleans where the food was good to very good. Seasoned, hot, fresh tasting. Both cruises were Carnival within 1 year of each other. Many shared dishes and entrees like the tomato topped fish they had on the buffet.
It's not that food "taste" is only subjective, I think the ships and who's prepping/cooking the food matters VERY MUCH.
Unfortunately its a roll of the dice if the food will be good or not when you sail. Other cruise lines I've seen are the same. The entire industry as a whole has taken a hit from Covid. You have to accept this risk when you book a cruise.....