You claim that 26" is far less common than it was a decade ago and that claim is just a straight up lie. 26" is as globally common as ever. It's just not as well stocked at your local bike shop because of MTB trends. Have a catastrophic flat and any big retailer will have a 26" tire that will work fine and cost little.

S7s are made by both CST and Kenda and can be at your front door tomorrow.

So having three hundred choices online and easy local access to 26" tires planet-wide seems like there should be zero reason to avoid the size simply because the wider variety takes one day to arrive.

You're viewing 26" through a MTB trend lens which is your big mistake.