The poker element is important as it helps get past the artificial boundaries put up by Meredith by resigning the decision up to "fate." The dev could've been lazy and just had the game be played through dialogue, but he instead decided to implement an actual poker mechanism and add it to the game, which I can appreciate.
As to your comment about the actual game being poker, this is a common minigame added to both NSFW as well as SFW games. It is likely people already know how to play this, and if they don't, it is easy to learn. My only criticism here is actually the fact it is so common. I think it would've been fun to implement a less common two-player game as poker is used quite frequently. However, I don't think "Strip Cribbage" ("Strippage?" "Stribbage?" lol) is a thing so it makes sense to keep it to poker for several reasons.
I can appreciate your argument about it being mandatory, as I dislike progress blockers that are based on RNG (which poker is). However, I may be wrong but based on the dialogue options with Scott, it seems like there is a way to cheat during the poker game. This would mean the game is not actually mandatory.
To sum everything up:
- Strip poker is important to the storyline
- The dev spent extra effort implementing it within the game
- The dev is adding game elements to a porn game
- Poker is a commonly added minigame and is relatively easy to learn
- The minigame itself is likely not mandatory