There is a difference between having a full tray and having an overloaded packed tray, which as you've said will cause a lot of steam in the air.
What does the recipe call for? They will often tell you 2 trays if there is more than a single tray can comfortably hold. Is there a lot of wet marinade? Is it a dry rub? Is your tray smaller than what they've suggested. Is the tray bigger than suggested. Have you doubled the recipe?
Only you can answer that question. If you are changing anything, it is you that has to make the judgement call.
As Chef John would say -
"It is you who has the say,
In what goes on your tray."