X6 has some really bad level segments in some places. It was not thought out at all. It was a failure in level design, and in engaging difficulty.
You'd be surprised. I'm not going to defend the garbage compressors, they're not my favorite either, but I've seen a LOT of X6 obstacles receive unjust complaints as being impossible. Perhaps most infamous is Metal Shark Player's alternate route; few players realize you can clear that with Hyper Dash alone. Which you need to reach it in the first place, unless you know how to work dash-jump speed physics to their fullest. There's more skill to the game's obstacles than most players realize; they just give up too easily in light of the game appearing sloppy presentation-wise. Many do not believe that it is even possible to clear Gate's Lab unarmored, which I have done. Hell, I know people who have claimed that the vertical lava chase in Gate's Lab 1 cannot be cleared without an air-dash.
I'll gladly take grinding with Dynamo Spitz-Swallows over X5 leaving numerous heart tanks and armor parts flat-out impossible to reach as a particular character, to say nothing of the obvious fixed order to the bosses and even the armor upgrades (you cannot obtain Gaia without Falcon), leaving the Stage Select screen as little more than a courtesy for those who have a favorite special weapon. Furthermore, you don't really need to "grind" to get an acceptable number of souls for using parts in general in X6. You have to suck pretty badly at X6 to not reach Rank A very quickly. The Limited Parts require GA, yes, but they live up to their name anyway in being one-shot deals and, besides Life Restore and Overdrive, not terribly impressive. The earlier is a free Sub Tank (see below), and the latter is over-powered against bosses thus justifying its late entry.
No grinding for parts, money, items, etc.
Filling Sub-Tanks mean anything to you? Or stocking lives for the secret capsule?
Sure, you can ignore it if you're actually good at the game, but it's still there.
Also, bringing up X5 again, you must repeatedly suicide for 4-6 game hours if you intend to get all the parts possible (which is never more than half). It's an odd kind of grinding to simply build your stage entry count, for sure, but it is without a doubt the most pointless X-series obstacle to ever exist.
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