Oof, what a subpar construction. 21 across ('Not worth a ___') is just too obscure for a Monday no matter what, and same goes for 15 across ('Kind of tide'). Then there's the hyuk hyuk theme (particularly unfond of 17 across, which is classic 'NYT constructors are a certain kind of people' moment) and another appearance from one of my instant eye roll fills, the use of 'NO TAR' which has shown up like sixteen times in the last two weeks of crosswords.