No it doesn't. Beam steering is adaptive and will work with signals getting reflected, for example. It's just noting where the return signal from the phone comes on 8 antennas and then narrowing the signal to the phone while increasing bandwidth. It does not use location (because it uses wave interference the "location" these beams is an interference pattern, not a position in cm)
Phone triangulation works by getting signal strength on 3 or more towers, and getting location from that. That's how it works on WiFi as well. Access points see the clients, and each other, and if you have enough data points, you don't even have to configure the locations of the access points. Of course, the location you get back is relative to the access points and the distance between them, so systems provide a quick way to convert to distances based on one or two measurements.
So please don't think 3G is going to protect you from triangulation. It isn't. Now they're decommissioned but even hospital pagers can be triangulated (some of them aren't even 1G, though anything remotely recent is just a cell phone in disguise)
Because of the "emergency services" mandate from governments it works without the sim being registered. Phones MUST be able to immediately call emergency services so sim or no sim, they are registered on the cell phone network using the number of the cellular modem hardware in the phone, the IMEI number. Phones without a SIM or eSIM can be triangulated. Phones that have never had a sim can be triangulated. Phones that had a sim, but now don't (you keep your phone on but have taken the sim out), can be triangulated based on the phone number of the sim (by looking up the IMEI that last used that SIM, then triangulating the IMEI). These systems can track mobile phones as they move, even in places where the signal is so weak phone service doesn't work (though of course, this doesn't exactly help with accuracy)
Of course whether all this works depends on the competence of the large telcos and the police in a specific country. What I said above is what's possible, not what is actually done. What another poster said is true: telcos have internet portals, accessible to the police (and ...) where you enter some information and get location back. This is generally demanded by governments, as the telco is not allowed to know WHO gets tracked by the police in most countries. Yes, in the US telcos are allowed to know, and they can even legally refuse to track someone, but in most of the EU this is not true.
Whether airplane mode prevents your location from being monitored depends on the phone.