Instead of my usual (twice yearly) overland biking to PP, had to, due to the land border closure, fly to PP. I normally take Thai Baht with me (except for a small amount of USD) as the exchange rate for the Thai currency is excellent in PP (and a couple of other big Cambodian cities)
On the off chance that the current hatred for Thailand extends to its currency, I purchased a larger amount of dollars at SuperRich Suvarnabhumi.
Today I went to Ly Hours exchange, they always have excellent exchange rates, and put 5000 Baht on the counter to purchase Riel. They refused.
Later on I passed another branch of Ly Hours, thought I give it another shot, and to my surprise, they did accept them.
Not sure how widespread the non-acceptance of Baht is at the moment, but if you are planning to visit Cambodia in the near future, it might be a good idea to bring $ too.