Considering the celebration part you’re right but since Celtics is thirsty on championship, I really doubt that they will wish for a 1 loss while they are 1 game away to their ultimate goal. They can always celebrate at Boston whenever they want
Celtics could not give Dallas a chance to beat them as anything can happen although there's no team yet that we able to come back from 0-3 deficit. IMO, it's okay to end the series at the home court of Dallas than risking their chance of winning the championship. We will know tomorrow if the Celtics could finish the series, but in case they'll fail, there's like 90% they'll win in game 5.
I was hoping that the series will be longer, but here it is, just like the last NBA finals, it remained boring.