It actually happens quite a bit when bombing with certain loadouts. Take a normal gremlin arena with the loadout-
Chaos set
Ash of agni = counter most everything that isn't a mender
Venom veilor = counter menders
Some gun = be able to deal something that isn't crowd control
If you make some gun phantamos, then the trojan could kill you easily or the turret type could be howlitzers.
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Other times it is a specific level presenting the problem- compounds can have fiends + slimes or undead + gremlin or beast + construct. A lot of the harder end game levels also benefit from normal damage as a type- assault on grinchlin mountain and dreams and nightmares being the two. Both of these levels have a huge variety of enemies; bringing any form of support weapon (or on type damage that does not counter all of the enemies, like scintillating sun shards vs grievers) can make for a situation where normal damage is the only type not resisted/worthwhile.
"Overall, normal damage can be underwhelming but specialized damage is even more underwhelming when you're stuck using it on enemies that resist it, and you can't always afford to give up extra slots just to get that extra bit of damage."
And how frequently do you get stuck having to use it against enemies that resist it? Seems like poor choice on your part given the available information to predict depth monsters.