Most religions were documented long ago and tend to polarize into good and bad.
The entertainment industry 'money in exchange for fun' typically falls in the 'bad' box.
Gambling in general and poker as part of it can have bad aspects; addiction, losing money that should have been used for food or education.
I've seen friendships break when the friends started to play a card game for money.
If playing poker is for fun, without busting any budget, it's the same as paying for a music streaming service and shouldn't be considered as a sin.