I don't think glitches are necessarily bad in fighting games (the combo system in Street Fighter 2 resulted from a glitch and look at how prominent combos are now) but I haven't actually played Melee, so I can't say whether that applies here.
The titles could use some work, though it probably isn't a big deal.
"A twenty year old fighting game had glitches so this should too!"
If the game was designed to have combos and shit like that it would have them. When your "mechanics" are exploits in this day and age, it's poor game design.