Potty training

My son is 2.5 years old and was fully potty trained as of May, he went consistently and told me every time all of May and June. Then July came and he had a regression (which I know can be normal) but it’s coming to mid August now and he has been having accidents everyday all day. He’ll go in the potty once a day, maybe, sometimes not at all.

I need advice, if you were in this situation would you let the regression happen, go back to diapers and wait it out a little longer? Or would you continue with putting him in underwear knowing that you’ll have to clean up accidents all day to keep the consistency?