@Mogthor think of each Blender version as a separate tool to complete a task.
You could use whatever tool you like, but when learning it’s best to use the tool the instructor is teaching with,
Learning CG becomes much more efficient this way, as the frustration of UI and other behavioural changes will be eliminated.
A trainee mechanic for example, will start learning their trade using traditional tools,
only when more experienced do they then get to use the the fancy high tech modern tools.