For the full nostalgic computing experience, original hardware, preferably plugged into a CRT screen, is the ideal. But as with most ideals, that experience can be fleeting or vanishingly rare because a natural consequence of age and "made to a budget" materials, this stuff breaks down. Unless you have a large budget you must develop the required skills + carve out time + collect spare parts.
You need to have a passion for retro computer repair and maintenance hobby as well as the retro computing hobby.
I have a growing pile of "repair projects". Some of which started out in my collection as fully working.
Don't get me wrong, I do fit into the category of treating the repairs, and especially the investigative/troubleshooting side, as a hobby in its own right. Heck, part of the reason I got into electronics and why I've learned much of what I know is due to the need for it. It's not all blinkenlights!
But the main reason for my retro computing is programming, and I have to wonder if the community needs to get passed the "original hardware or GTFO" gatekeeping even when it comes to developers, and for sure for retro gamers.
People who just want to play games absolutely should not be shamed for using recreation or emulation. I'm firmly decided on this point. I don't care about minuscule lag or inaccurate CRT effects, let people play their Mario in HD over HDMI using a wireless XBox controller if they want to!
But I am also coming around to the opinion that, of course your commercial game should work on original, physical hardware, the hobby retro game coder shouldn't be forced into the same category.
FPGA, such as MiSTer and Spectrum Next, and the most popular emulators in my experience are plenty accurate enough for a community release. I'd imagine most of the game's players will be using those systems too!