"Is it safe to assume that ALL airliners are equipped with this technology? 7X7/A3XX/MDXX ?"
The 744, comes in lots of different flavours...
Ones without any detecting probes.
Ones with a single ice detector, but manual operation of anti-icing.
Ones with two detectors and a fully automatic anti-ice system (Wing and Nacelle).
Others with detectors, auto anti-ice for nacelles, but not for wings... etc.
The ones with detectors have them mounted on the nose below the pitot/static probes.
Rgds.
NSEU.