If you ever come back to the UK you'll be rather impressed. Pretty much everywhere accepts Contactless now.

Contactless POSes aren't really a thing though apart from Santander I think.

I believe the OP means POS as in Point Of Sales. Santander tends to have ATMs, as in Automated Teller Machines :)

UKs implementation of contactless is still behind other countries in the EU. In most other places I can use contactless to pay any amount, the terminal will simply ask for my pin if the transaction is over the pin-less payment threshold. In the UK that's impossible - even if the terminal displays the contactless logo when you are attempting to pay over 30 pounds, if you attempt to use your card that way it will just beep and tell you to insert the card. I'm guessing it's a peculiarity of UK banks which decided they would rather disable this system even though the terminals do technically support it.

That's not entirely correct. Some countries (e.g. Spain) have no floor limit and request a PIN, others use the same system as the UK (e.g. Germany). Wikipedia has a detailed list: https://en.wikipedia.org/wiki/Contactless_payment

I think the major complaint is (never tried paying contactless in the UK, no clue if that is correct) NOT the limit that doesn't require a PIN, but that you have to start from scratch and use a different method (insert card, provide PIN) if you cross that threshold. If that's true, that sounds like a UX problem and I'd hate that as well.

Here in DE it's not like that - or at least never happened for me. A transaction that I start contactless might (random verification or > threshold) require a PIN. But I never need to insert the card or get an error message like the GP described.

It is absolutely a UX problem. In the UK terminals will show this image:

https://cdn.barcodesinc.com/images/models/lg/Ingenico/ipp320...

Even if the amount is over the threshold - only once you tap your card on the terminal it beeps and says "insert/swipe card". Why even show the contactless logo then????

Not all do but the majority. I believe it's the manufacturer's fault, not the bank's (or store). But I guess in devices like this, pushing a software update to fix a non-critical UX flaw could take years.