You can't mod anything outside cosmetics and state in bedrock, whereas you can mod everything in java edition.
Do you get something for that? Sure. The first six months I played MC Eternal I was still finding random drops from mods I'd never seen before, I fought monsters yesterday I didn't know existed last week. And beyond suspecting that the moon is actually literally made of cheese (thus explaining where the rat civilisation went) I haven't even started on space travel yet.
On a PC you can run a large pack slowly on a medium sized PC, or reach inside and (for solo play) rip out the biggest pieces you care least about. Neither of those sound practical for a Switch.
I'm sure a PS5 could run most packs if somehow they were functional, but I'm also sure most Minecraft players don't have a PS5.
Mojang made the original version (now called Java edition).
Mojang then made Pocket Edition for iOS, and made it as a separate thing with no cross-play.
Mojang then got someone else to make the Xbox edition, again it didn't cross play with anything else.
Then Mojang sold to Microsoft.
Microsoft then made the iOS, Android, XBox, Nintendo Switch and Windows 10 editions all work together and have the same features and upgrade path.
So its not really fair to say that MS trashed the interoperability aspect - it was Mojang that started down the path of different versions for mobile/consoles. MS actually did a huge amount of work to make all those platforms work together again.
But yes there are now two seperate Minecrafts - Java edition, and all the others (previously known as Bedrock).
Its better than it was though, in interoperability terms.