The Steam page says it will feature single-player, multiplayer, cloud saves and achievements.

The GOG page only lists single-player.

What gives? Are these features actually absent, especially multiplayer? Or is this just an error? I don't feel comfortable buying something praying for it to actually have features I expect

It lists them all: https://www.gog.com/en/game/star_wars_episode_i_jedi_power_battles

What the hell. It said the sale would last through January 24. It's January 23 and the sale is over. And only now they updated the information that the game does in fact have multiplayer.

This isn't how you get people to buy games. This is stupid and annoying. I last played this 25 years ago, I was in no rush to buy this and right now I'm not feeling it