I think the direction that Microsoft are taking Minecraft is really disappointing. As a Java player though I really enjoy drawing and customizing my own skins, Roblox's customization options are limited and more often than not require the purchase of items through real world currency in the form of Robux. Although anyone with a credit card can customize in Roblox, people who don't know how to skin still have the ability to franken skin (fuse peoples skins together) for Minecraft.
Anyway I talk about these customization stuff because maybe I'm cringe but I like to make skins for OCs. With that said Roblox customizability options are just not up to par, also their chunky character models are gross, Minecraft is definitely the lesser of two evils when it comes to models.
When it comes to the ability to play unique game modes (which is the only thing you can really compare) I think datapacks have a lot of unreached protentional and mods are another way to recreate the unique game modes, not to mention some of the crazy plugins people develop. it's a shame there is not as much an audience for more niche game modes unlike with Roblox.
At the end of the day I'm bias towards Minecraft, since Roblox is aimed at a younger demographic and I've only tried it a couple of times but I very much my prefer Minecraft.
