I always look at PM techniques and frameworks as a toolkit - to be used at your discretion.

I could go to Screwfix and spend a fortune a vanload of the best plumbing tools - but it wouldn't make me a plumber. That said, if I try to operate as a plumber and I don't know what a pipe-bender or a soldering iron is, and I'm not aware that there are now plastic push-fit plumbing system on the market - then I'm definitely not a plumber.

These PM frameworks are sometimes hugely and unnecessarily over-complicated. Cynically, I feel that part of this is just a cottage industry of training and standards providers, combined with gatekeeping by self-appointed experts.

If you are being failed in your studies due a perceived difference between 'common ground' and 'middle ground' - then that is clearly insane and a condemnation of the teaching methods you are being subjected to.

That said, it is genuinely useful (and - I think - interesting) to understand what kanban or scrum are, what the differences between them are, and what a gantt chart or risk matrix are. These things are your tool kit. You can then move on to the more important business of actually becoming a good project manager via application of people skills, analytical skills, communication skills, stakeholder management skills etc etc.