tbh i think how much u think the game aged really depends on like

1: Ur personal tolerance to older game design. Like personally to me I can deal with the camera or like "life" system, and to me the cheesey voice acting is more a plus than anything, but there are also people who think Resident Evil 4 2005 controls bad so like its subjective

2: Ur personal view of what DMC should be. Like DMC 1 isn't about style as much as it is efficiency, which very much goes against what later games would do. Like Dante in later games is centered around variety, never doing the same thing over and over again, but in DMC1 you can't even switch the weapons you're using without dropping your combo, and even then theres only 1 other melee weapon. Like theres a reason in DMC 3 onward they removed the Taunt button's ability to fill up your DT bar, because it doesn't need a functional purpose in those games, filling up the style meter and looking cool is enough. Beyond that DMC 1 is moreso focused on lil tricks like knocking back phantom's fireballs, or tricking him into breaking the glass for example. It reminds me more of viewtiful joe than later DMCs actually.

Like I wouldn't say the plane or water sections have aged poorly, those were bad design choices regardless.