Not entirely true. While the apps don’t work, for manyyears, maps.google.cn remained accessible which also redraws the lines like the 9 dash line and shows Taiwan as part of China.
It is still accessible and people (I’d reckon outside China) maintain some data for restaurants and other locations.
If you use a Taiwan SIM roaming you can access Google/Facebook etc., not sure about other countries SIM’s. Don’t know about now as, for obvious reasons, it’s been a couple of years since my last trip!
Yeah, roaming tunnels to the original country’s internet. You’re not actually on the Chinese Internet.
You can also make other devices tether to your house’s Internet by setting up a VPN server in your house and since China doesn’t know the addresses can contain access to sensitive information, it’s unlikely to block them.
I set up my own vpn when I went to China in '18. Accessed Maps and it listed tons of restaurants and places and all. Could hardly tell it was banned there.
Whether you are or are not on Chinese internet using a foreign SIM card, in the absence of a VPN, the Chinese censors are still in complete control. They can, and do, turn access on or off at will and the level of “openness” also depends on where in China you are ~ you may be able to access Facebook in Shanghai but not in Jilin.
Google maps was available in most places in China in 2008 without the use of a VPN as it wasn’t banned at that time.