True but there's also the MAC address...

You are right, you should definitely not feel safe when using a generic network name. In the file that OP posted, the MAC address was missing though. Doesn't mean that it wasn't present on the device. Android used to write the MAC address to logcat, nowadays it's off by default. Sometimes the MAC address of a network gets stored to wpa_supplicant.conf. I'm sure that NetworkManager reports the mac address in journald as well.

This can be spoofed I guess?

Yes

macchanger (I use a custom script that works better for me. Also does magic in places with limited interned, e.g. free 100MB limit)

You would want to look at a database of the most common MAC addresses and SSIDs (maybe even pairs of them) and spoof your MAC address and SSID to match one of the most common pairs.

But it won't help much if there are any other wifi networks or devices around.

"McDonalds Free Wifi" and a MAC address swiped from a nearby (but not so close your Wi0Fi signals will intersect) Mc Donalds...

For enhanced sneakiness, deploy three or more Wi-Fi base stations at the same location with the radios tx power turned right down and directional antennas - and try to make the geometry lookalike it's just a lucky long range shot to a real public/free wifi behind the antennas...

SSID is not significant. You can use a Google service to get a location, and what you need to supply is 3 or 4 mac addresses, not SSID.

Yeah it's returning 502 Bad Gateway errors (AFAIK that's what a CDN would return if it can't reach the actual host), probably a HN/reddit hug of death?

I just realized people can track my relocation across cities and countries if they can see "Ah this SSID was there last month, and here this month!".

My parents moved countries, bringing their WiFi router, and for months afterwards their iPhones would locate them back in the old country... Apple's database was quite slow to pick up the new location.

That's a bit of a simplistic programming, the phones should've seen other SSIDs around it and figured out they're not in Kansas any more. Except if your parent's WiFi network is the only one around the area.

They should be aware that some wifi channels are not legal in all countries.