In server areas and extremely specialized stuff? Yea, sure. But we’re talking desktop PCs here.
Many houses run circuits that are rated for 20 amps even if they don't have the right outlet for it so this is an inexpensive upgrade for most.
It's the difference between NEMA 5-15 and 5-20: https://en.wikipedia.org/wiki/NEMA_connector#NEMA_5
I think this is mainly because the 20 amp outlets are kind of ugly, and the fact that barely anything actually uses a 20 amp plug.
In my house, almost every circuit has a 20 amp breaker and 12 ga (yellow) romex, but only a couple of outlets are 5-20.
I can buy a 10-pack of nice 15A Leviton Decora Edge outlets (that use lever lock connectors instead of screw terminals) for $26 ($2.60 each), but basic 20A tamper resistant outlets (which newer editions of the NEC require anywhere a small child can access them) are $6+ a pop.
When nothing outside of my electrical room (where the servers live) has need of a 20A receptacle it's kind of pointless to spend the extra money on them, but the extra couple bucks on 12 gauge copper is always wise.
If my understanding is correct, then you overkilled it and you could have saved a few dollars, at least one welli-intentioned rant, and still have been compliant with NEC.
A literally-single 15A outlet like a Leviton 16251-W would not pass muster, while one dual-outlet example of the 15-amp lever-lock devices you mention would.
I had the luxury (or curse, depending) once of owning a home that needed all of the wiring replaced.
Being the kind of person that I am, I overbuilt things as I felt was appropriate. As part of that, I certainly wanted to install 20 amp outlets (even though I've never held in my hand a 20 amp plug).
The cost of that, vs good spec-grade 15A duplex outlets, was insane.
I know that the only difference is using one T-shaped contact instead of a straight and some different molds for the plastics. The line producing T-shaped contacts already exists, and so do the molds. Every 15A outlet sold today can transfer 20A safely.
It should be pennies difference in cost, and it was instead whole dollars.
Sucks.
(I'm reasonably certain that we are going to be broadly stuck with this low-current, low-voltage business until something very different comes along, and that any of this is unlikely to change in my lifetime.)
Electricians will almost always install 20 amp sockets where they can, but they avoid running 12 gauge wire because it costs about 50% more.
Most of the US utilizes the NEC for installation compliance. Per NEC, 15A-style outlets are "to code" on 20A circuits unless a single recepticle ("dedicated") circuit — in which case a 20A-style recepticle MUST be installed.
For any electric appliance (including computers) which operates for 3hrs+ ("continuously"), the circuit rating is reduced to 80% capacity (e.g. only 16A load allowed continuously on a "20A circuit" == only 1920W computers allowed on 20A circuit, 1440W on 12A).
Pro tip: check your own PSU, but practically all modern computers can handle AC input 100-240V (all you need is the correct IEC power cord for a 240 US plug).
I have fixed enough melted devices in my career to always twice-torque each&every connection I make. For temporary extension cords/plugs, "twist lock" ends are worth all the extra dollars.
Protips: use Eeez-Ox (a conductive paste which inhibits corrosion) for high-load applications (non-data, only). My own gamerig's AMD GPU has it (sparingly applied) within its dual 8-pin connectors. I supply the 8-pin connectors from a single pair of 8awg copper, which is directly soldered within the PSU's PCB power-take-offs... so only a few inches of 16awg for voltage drop (into the GPU), which reduces the amperage required (but is also unnecessary overkill).
That's a new one for me. Do you have a reference for that? I'd love to read more.
As trade practice, certain applications are ALWAYS deemed "continuous," e.g. water heaters, computers, space heaters, general lighting.
... do you not have electric kettles in the US? Foolishly, I thought this was a standard kitchen appliance all over the world, I've even seen it in smaller cities in Peru.
There's aquarium heaters on amazon that say they're 10kw or more and plug into a 120 outlet.
I bought a magnet that is supposed to hold "150 pounds", but pulls off the ceiling (in it's strongest position) with just 10-15 pounds.
Amazon specs are fake.
Many parts of the world, it’s a good idea to boil water before using it for drinking, brushing teeth, etc.
So it’s actually really convenient for many use cases besides tea or coffee.
We could even use 240v electric tea kettles here in the US if we wanted to; most kitchens with an electric range and oven have 240v (or 208v) outlets to plug them in to. But those outlets are usually inconveniently located for counter–top appliances. It wouldn’t cost much to add another above the counter, but it is rarely done in practice. Of course, in many parts of the US natural gas heating is cheaper than electric so the houses there are built for gas ranges and ovens instead.
My solution to drinking a cup of tea is also unusual: I have a no-longer-in-production Sunbeam Hotshot and I use it heat only as much water as I need right now.
It raises one tea-cup worth of water from whatever temperature it is that comes out of the cold tap to boiling in about 40 seconds.
I just dump a cup of water in, push one button to heat it up, wait until it boils, and then push another button to dispense that hot liquid into the cup that I'm using for tea.
It then turns itself off until next time.