Minecraft Java Edition has always functioned pretty much the same way since developer Mojang's acquisition by Microsoft. Bedrock Edition came along to integrate with the Microsoft account system, but Java has been operating on its own Mojang account island - until now. Java Edition will soon require you to sign up for a Microsoft account in order to play. However, you'll receive a free cape.
In the early 2021s In the beginning of 2021, you'll have to transfer your Java or Mojang account to the Microsoft account system. Mojang states that this is to introduce two-factor authentication to provide increased security, though it'll also bring better parental control as well as chat and invitation blocking and account integration with Minecraft and Minecraft Dungeons.
As for Minecraft mods and PvP, Mojang states that nothing will change. Java and Bedrock will continue to be completely separate games. You'll continue to be able to play using your current Java username, though in the event that you're creating a Microsoft account for the first time, you might need to change your account's name. MINECRAFT SERVERS can merge your Minecraft sign-ins if you already have a Microsoft account.
To make it easier to cope with the switch, Mojang is giving away the once Java Edition's most sought-after item that was the cape. Participating in the migration will get you a free cape. Although it doesn't come with the Minecon exclusive designs, it will let everyone feel a bit royal.
While nothing is likely to change, players do have concerns. For instance, the more restrictive terms of service by Microsoft might lead to bans and could result in some players being denied access to Minecraft.
Further details can be found in the official announcement and FAQ. We'll see how it plays out in 2021, in the beginning of the year.