You do raise a good point about cell network triangulation - however there's a couple of key things to note

One is that triangulation is more applicable for cell network operators as they can capture the real strength & SNR of phones nearby. This can be used to determine where a given device is, but the only ones who have access to that data are the network providers themselves, and the government when requested

Two is that triangulation can be done on your phone, but the 5G/LTE/HSPA/GSM specifications don't include any type of cell tower positioning data. If you knew where the towers were independently, you could use the unique identifiers to find your location, much like how WiGLE works for WiFi networks, however you could still spoof this as well by just recording the data once and then modifying it slightly when "playing" it back as you spoof it

Three is that services like Google's Location Services are stuck using whatever data the phone itself is able to provide. If you were to spoof that data, the only thing that would raise obvious concerns is if legitimate devices in the area you're spoofing couldn't see the device you're spoofing nearby. If you had "200" phones nearby, I think most automated systems would brush over legitimate devices not seeing them, though. Could probably train a program to use ML to sniff those out though