Oh, there's definitely a certain charm and feeling you get running a game or other piece of software on the hardware it was originally built for. I personally have had a GameCube for a while because there are certain games I prefer to play with the old hardware, and for the fact that it was my first ever console growing up. I'm even looking into retro PC building for older games I never got to experience in their heyday, but still want something approximating the true feel of them, even if it's just their campaigns and not their multiplayer - the Quake series, for example, or the original Unreal. And that's not even getting into the games that are notoriously difficult to emulate, if someone wished to go that path. Compatibility issues, visual bugs, framerate desyncs, control oddities that weren't present in the original, all things that you'll probably have to deal with at some point if you emulate more than a few games.
However, that doesn't mean emulation doesn't have a place in this sort of thing. There are rare games that are difficult to find that you may wish to experience in some form or another, or are prohibitively expensive due to the aforementioned rarity or just being such good games that it's hard to find someone with a physical copy who'd be willing to part with it, or even use it to preserve the original format the game was in at release. Castlevania: Symphony of the Night comes to mind, for the latter category, and any Pokemon game that's no longer in production would certainly qualify for the former. Or, you yourself are a collector, and don't mind dealing with a moderately buggy emulator to keep your games in the best condition possible for the purposes of preservation, only actually using the disk or cartridge for special occasions. All completely reasonable and understandable explanations for using an emulator over original hardware, and all perfectly fine as long as you aren't pirating a game that the devs can still see money from. For example, if you emulate Pokemon Red, a game that's not been in production in almost 25 years, is ridiculously expensive, and all the money from buying the legitimate physical copy would go to a secondhand seller?
tl;dr: It depends on the situation. If it's not prohibitively expensive or hard to get, and I can accommodate it, original hardware is great for older titles. But if it's a ridiculous ask to get the game, due to price, rarity, or both, there's no harm in emulating it as long as you're not stealing from devs.