Geyser sounds very interesting especially if you know some or all players wouldn't be willing or perhaps able to play Java Minecraft and so they have to run Bedrock, but some would play Java and they'd enjoy being together.
Java Minecraft is just a better toy, I'm not altogether sure it's a better game, depending on how you define game, but it's a better toy because it's so flexible. I assume Geyser can't magically donate much of that flexibility to a Bedrock client, but if the players can co-exist then that's a boon in itself.
Aside from being more flexible they are mostly the same game. The original excuse for bedrock was that Java was slow and a native game would render much better, it was also easier to put shaders in a a native codebase. But Java edition is pretty performant nowadays and computers also got much more stronger than the game became heavier