I'm "guilty" of that myself: I ordered the Duo because I really want a PC Engine system, even though Mesen is a perfectly fine emulator and I probably don't want to play my original HuCards anyway out of fear to eventually break them.
I think the N64 might be in a bit unique situation because all the emulators for it are kinda crap, which is why I was surprised to see an announcement of an FPGA version. But I also saw a breakthrough recently in the MiSTer project, so I guess it's finally time - and if they really managed to re-create the Silicon Graphics GPU, I'm impressed, because even though it's 25 years old, a 3D Graphics Chip is still quite a feat.
One thing that FPGAs can potentially do better is to emulate the entire system without needing a crazy PC. Stuff like "A memory fetch takes two clock cycles, but actually, the first clock cycle leaves garbage on the bus, and if a Sound DMA triggers, it will fetch that garbage, and that is actually required for Game X to work well". (There was a GameBoy Advance emulator that found something among those lines being the reason why one of the Pokemon games doesn't work properly in an emulator. And I remember there being one SNES helicopter game where the shadow under the helicopter never showed up in emulators of the time, because it used some crazy exact timing to render it on original hardware).
Doing a cycle-exact simulation of an entire system is pretty hard (All the "How to write an emulator" tutorials just do a big switch statement of CPU opcodes and call it a day), and it's harder the more advanced the system gets. So an FPGA still has the _potential_ to be a better implementation overall, but it's always going to be that system that's "Accurate except where people want anachronism" but always limited in what kind of additional enhancements it can make (HD Texture Packs, CRT Filters, Retro Achievements, Local Multiplayer over the Internet, with matchmaking)
I think most emulators are fine for the big "brand name" games like Mario 64 and Zelda Ocarina of Time. I played through both on an emulator without any issues as far as I could tell.
Where most emulators still kind of suck are the later N64 games that really exploit the hardware, like Resident Evil 2's FMV. As of about a year ago, RetroArch with AngryLion actually does emulate that correctly, and I managed to play through most of the game without any issues, it definitely pushes my relatively beefy laptop to its absolute limit, and the only cycle-accurate N64 Emulator that I'm aware of, CEN64, only runs at like 4 fps on my machine.
I too am interested in seeing if the MiSTer can pull it off, because that would definitely work in favor of proper preservation of a lot of the later N64 stuff.
If they can pull it off, it would be a massive achievement, even though I personally can't think of a single N64 game I'd actually still want to play personally.
Honestly, I do think the N64 is definitely a mixed bag; there's some real gems on there (Super Mario 64, Zelda Ocarina of Time, Conker's Bad Fur Day, Banjo Kazooie, PilotWings 64, Perfect Dark), but I think pretty much all of the excellent games have more or less made it to the Virtual Console or Switch Online thing.
However, there are a few games on the N64 that never really made it to "legendary" status, and as such never got any real updates/modern ports, but are still worth checking out. Space Station Silicon Valley, for example, is a very unique and interesting game that's a lot of fun to mess around with, and the only "port" that got after the N64 was a terrible one on the PS1. The N64 was one of the earliest (popular) 3D-first consoles, and as such there's a lot of interesting experimentation going on that I do think is genuinely worth checking out.
That said, it's kind of hard to recommend the N64 to anyone; for every Mario 64 or Banjo Kazooie, you have three or four extremely bland mascot platformers (e.g. Gex 3D) or uninspired racing games. It's an extremely mixed bag.