Georgia offers visa-free entry to Americans and Canadians, EU citizens, Russians and now Chinese with ordinary passports.
Are there any other countries or regions with a similarly welcoming policy to travelers from all those groups simultaneously?
Georgia offers visa-free entry to Americans and Canadians, EU citizens, Russians and now Chinese with ordinary passports.
Are there any other countries or regions with a similarly welcoming policy to travelers from all those groups simultaneously?
The Maldives has probably the world's most generous visa policy: anyone, regardless of nationality, is welcome for 30 days as long as they have a hotel booking or sufficient funds, plus a return flight.
Svalbard allows literally anyone of any nationality to enter and live in Svalbard indefinitely, as long as they can support themselves and aren't breaking any local laws.
The caveat with this is that it's hard to get to Svalbard without going through the Schengen area, which will require at least a Schengen transit visa if you can't be waived through. Perhaps once things settle down in Russia, (chartered) flights or ships from Murmansk are an option again, if Schengen is the thing keeping you from entering Svalbard. See https://travel.stackexchange.com/a/184278/287 for details.
Using strictly Wikipedia as a source, and following the procedure suggested by @xngtng (starting with the most presumably restrictive citizenships), I come up with about 30 countries that meet the original requirements. HK and Macau are a bit tricky because of the defacto e-visa so I have not included them.
Angola
Antigua and Barbuda
Bahamas
* Barbados
Belarus (not at land borders)
Bosnia and Herzegovina
* Dominica
Ecuador
* Fiji
Georgia
* Grenada
* Haiti
*Jamaica
* Kazakhstan
* Kiribati
* Mauritius
* Micronesia
Morocco
Mozambique
* Oman
Qatar
* Saint Kitts and Nevis
Saint Lucia
* Samoa
Serbia
Suriname
Thailand
Tunisia
UAE
Uzbekistan
* Vanuatu
The 14 countries with an asterisk also allow visa-free entry for Indian citizens.
If we add Pakistan as well, only five countries remain.
Barbados
Dominica
Haiti
Micronesia
Vanuatu
Georgia stands out as allowing 1 year stay without visa for North Americans (including Mexico), Russians and EU citizens. As does Kazakhstan as being a very welcoming non-island country.
Are there any other countries or regions with a similarly welcoming policy to travelers from all those groups simultaneously?
Phu Quoc Island, Vietnam. They have a visa exemption policy for international visitors for a temporary stays of up to 30 days.