Manuel A. V. answered 10/31/21
Poker player and erudite
It's certainly an uncommon/uncanny way to announce a call - as a matter of fact, I've never heard in in my life till now but following the terminology, yeah. It is a call.
Generally, to "play the board" is used when there's a cards on the board stronger than the hand you've made or a certain similar scenarios.
For example: you have 2sKd. Your opponent has AsJc. Both of you are all-in.
The board comes 4h 5d 7s 3c and 6c.
You're essentially playing, almost all the "board" because you didn't even need to hit your pair/hit your K.
But even more often the terminology is used when you're using all the cards on the board rather to make your hand rather than the hand you've been dealt.
So let's say the board came 4h 5d 7s 6c then 8d.
In poker mechanics (talking about the most common form, 'Texas Hold 'em') was different, you could still use your K or 2 somehow, but you're automatically "forced"/forced to "use" (not literally) all the cards to find the strongest one. So your card automatically becomes all the ones on the board rather than the 2 or K you've been dealt because now there's a straight (5 cards on succession) on board. Your opponent also has nothing yet he catches the straight along with you because they're community cards.
Both of you "play the board".
-Manuel V. S.