Right, there are code compliant solutions. I was just musing over an idea of having 240V "everywhere" (including inside the house in every room, having 240V for special needs is, of course, a solved problem).

14-50R is not what I would use in that case, they are bulky, unsightly and don't offer tamper resistance.

6-20R / 6-15R have variants that are tamper resistant, and they look like regular outlets.

"20A should be enough for everything".

We used to have 2.5-3kW kettles before we moved to US, which would require 20-25A (although, I don't think the math is that simple -- circuit breakers don't trip on "exactly 20A").

Also, the issue with 20A receptacles is that, again, I have never seen 20A plugs (NEMA 5-20P) on appliances (it has neutral connector "flat" rather than vertical). Which is understandable, why make them if nobody has 20A receptacles anyway. There is a requirement to have two 20A branches in a kitchen, but commonly they are wired to 15A receptacles.

Your anecdote about coffee makers is a good one - it bears repeating that one of the most intensive household loads are old-school coffee percolators, etc., and many school and church kitchens have circuits just for them.

As for 20amp, it may interest you to learn that I have a commercial microwave with two magnetrons that is actually 20amp (and has the horizontal pin, etc.).

Yeah, it shows that I have zero knowledge about commercial appliances. I guess, I wouldn't be surprised if they routinely use 20A plugs / receptacles. Would make sense. Maybe, hospital equipment, too?

You would routinely see IEC sockets in use in Europe in commercial kitchens, factories, anything outdoors like a music festival etc. Partly it's for higher power appliances (including 3 phase power), but also the waterproofing.

They're also the socket found in datacentres (in Europe) to connect a UPS or PDU.

Home users see them at campsites, marinas, and for charging electric cars without a special car charger.

https://en.wikipedia.org/wiki/IEC_60309

I actually have a set of 4 20A receptacles within about 3' of me. I had to have an electrician wire a dedicated line, the main cost was the labor, might as well use 4-wire cable wired to 240V, I got 4 120V outlets out of it and he used the 20A type that takes either the usual household plug or the 20A version.

Wiring 240V is (typically) not an issue, as it is standard (in the US) to get 240V from the transformer to the house. The devil is in the details: what current would you wire it for, what receptacle are you going to use and what are you going to plug there.

ICE-powered pressure washers go up to 4,000 psi. I have never seen an electric pressure washer above about 3,000 psi and they're usually no more than the ballpark of 2,000 psi.