It's worth noting that FPGA is expensive and rather niche. The Spectrum Next was £300+ when available, the Amiga Vampire standalone €600, an Analog NT is c.£300-400 in the UK and all of these aren't available. Even a fully fledged MiSTer setup is c.£300 once you factored in the IO board, memory, USB hub, PSU and case etc.
Both the SNES/NES Mini and theC64/Mini use commonly available emulation software and have been praised for their dashboards/built in software. At least The C64 has had a number of firmware updates adding new functionality. So on this it would appear Retro Games can be trusted. Nintendo have the advantage of being a much larger company and owning all the IP. I do think the A500 Mini is a bit pricey vs their C64 Mini, but it comes with more in the box.
I did buy a MiSTer late last year and that has been my recent weapon of choice for experiencing Amiga. I do think it's probably one of the best options for people wanting to go the FPGA route, but there needs to be some realism, in that you aren't going to see a £120 FPGA console.
I've used WinUAE, Amibian/Amiberry, RetroPie, Pimiga and AmiKit (on Linux and Windows) over the years. Also have Amiga Forever 8 (I think 9 is out now). For me using these to play old games, or play around in Workbench (have 1/2/3.x and 3.1.4) there has been little discernible differences (latency being the main thing). The Amiga demos can sometimes not look as smooth but again it feels like nit-picking. I think for most people emulation is fine. Particularly for just trying old games. The Amiga can require a bit more cost and effort to setup than other formats. For example buying legal versions of the Kickstart and Workbench OS.
One main advantage of emulation is the speed. If you using something like HstWB Installer, emulation can compile installation packages much, much faster. And I imagine that would be true of programming and DPaint usage etc.
There are modern projects like AmiKit that are fantastic. Attempts to give the Amiga OS a more modern, and usable OS. There something to be said for it running on it's own box (whether that be a Raspberry Pi or whatever) and I can see why people mention the best Amiga is a Raspberry Pi. Obviously real hardware is very cool too, but will come with costs, maintenance, modern upgrades etc. And therefore not be for everyone.
Hope that helps.