Perhaps it may be because I haven't attained the T5/T6 masteries like Leyline Gliding or Adrenal Mushrooms, but at this point, having earned several T3/T4 masteries I can't think of the pinnacle of the mastery system as anything more than luxury masteries.

ArenaNet has been trying to push this idea of "Metroidvania" with retrogressive content, but there are a lot of ways to circumvent content that would otherwise require specific masteries using mechanics like consumable teleport/jump guns or rejuvenation/mango pies etc.

I suppose I'm rather skeptical of whether there's actually enough content that warrants the additional functionality of higher tier masteries and is actually highly rewarding/desirable for the time/effort spent acquiring said masteries.

Right now it seems like the higher T5 & T6 masteries have a very specific (limited) niche focus which clashes with their EXP requirements. You get much more out of the lesser masteries than the higher tier ones. I think a lot of the mastery debate condenses down into a simple, "I want" vs. "I need" and an inability to differentiate between the two because of how the maps value certain masteries over others.

The player-base as a whole seems centralized around "I need" because ArenaNet hasn't really shown that the higher tier masteries have the functionality to justify their enormous contiguous EXP sinks Right now, lower tier masteries (T1/T2) seem more valuable than (T5/T6) because they're more practical -- you'll get far more [gameplay value] out of updraft gliding & bouncing mushrooms because, comparatively speaking, you have far more opportunities to demonstrate mastery over these skills.

It's getting late so I apologize if this didn't make sense towards the end.