Can I play older versions of Minecraft in the Minecraft launcher

They will add 'play old versions' in minecraft bedrock edition : r/PhoenixSC

Minecraft now has one unified launcher on PC

Best Minecraft Launchers - Mojang, Curseforge, MultiMC, GDLauncher, ATLauncher — Eightify

If I delete my old Minecraft launcher do my worlds get deleted as well, or can they be restored by re-downloading the launcher? - Quora

MultiMC

Minecraft makes changes to some logos and icons, including a new Creeper launcher icon - Neowin

Minecraft: Java Edition Demo Mode

Change the Minecraft version on your server

Minecraft new launcher account problem - Microsoft Community

Java Edition – Minecraft Wiki

New Minecraft Launcher - How to Revert back to Original Launcher