I traveled through Lithuania, Estonia, Albania, Kosovo, and Greece this summer (July - August) and they were quite open and devoid of most tourists (exception was Corfu, Gr). Quite a few places were fairly lax where even masks were not required or worn (Estonia, Albania, Kosovo).
I would not say that Sweden was fully open. They were requiring a PCR test even for transiting passengers.
I would not say that Britain was open given the hoops and/or quarantine one needed to go through to travel there
I just returned yesterday from 11 days in Mexico and the country is wide open but they do have extensive masking and hand sanitizing.
Overall, in the current timeframes we are living in, it comes down to an individuals' risk tolerance since almost every country is going to have folks that go against the rules, there will be different levels of vaccinations, and different hoops to jump through as a visitor. I for one, knowing what my risk tolerance is, will focus my attention on countries where the hoops I have to go through are minimized.