In South Korea I recently only visited Jeju island. They have a lot of tourists there. There was lots of free wifi from businesses and some that seemed municipal. Fostering tourism might have played a role in that, I don't know. No clue how it looks like in the rest of the country.
Interestingly, the free wifi on Jeju typically didn't even have captive portals with T&C. They just let you connect.
In Singapore, captive portals are common. Cafes with free wifi usually require a password that you can get from staff by just asking. Municipial wifi is provided via Wireless@SGX https://www.imda.gov.sg/how-we-can-help/wireless-at-sg/wirel... at eg food courts and train stations.
I don't know if our telecoms have expressed much of an opinion. People still have mobile broadband plans.