It wants me to buy Minecraft Java Edition even though I already own the game

I was forced to mitigrate my account over to Microsoft from Mojang, which everyone was already annoyed with. And, I own Minecraft, and have been playing for years. I wanted to play a previous edition of Minecraft, but you are unable to change your version from the Windows 10 Launcher. So, on the Minecraft website I clicked the windows legacy launcher download, but then when I tried to play the game, it said I had to play in Demo Mode, and I didn't own the game?! That's ridiculous! I'm not going to spend another 30$ Just so I can play older editions. I HATE the new windows 10 launcher and game client. They took away SOO many options, You can't even use the F3 function to get information. I am just going to stop playing Minecraft at this rate, they took away SOO much from the game! All I want is the old Minecraft back, ever since Microsoft took over it went downhill, they just made it a moneygrab with the minecoin and buying all the outfits and stuff in the store, it's ridiculous! It's not even fun anymore! I already own Minecraft and am able to play through the Windows 10 launcher, so I SHOULD BE ABLE TO PLAY IN THE LEGACY LAUNCHER! I shouldn't have to buy minecraft again just to use the old launcher! It's ridiculous! 

My IGN is Quick Ag#7257

Either fix this issue and let me play in the legacy launcher or, minecraft is dead to me and I'm never playing again, because I was forced to migrate to microsoft, then I was forced to play in the shitty stripped down Windows 10 launcher! And, I can't even use half the features from before! Using the Windows 10 launcher is just irritating! I wish Microsoft never bought Minecraft, they just turned it into a money grab scheme. All they care about is making money from little kids playing minecraft and buying the stupid minecoin and buying things from the store.