Well I have line of sight to a 4G antenna from the front of my house, so can reliably get 120 Mb/s down plus 10-20 Mb/s up over LTE. That's less than my WiFi, but my home WiFi is faster than average for the UK (though would be considered slow in say Singapore).
Conversely I have family members both in the UK and in the US whose WiFi is frequently unstable on a Zoom call (while I have often done such things using a mobile hotspot from various places without problems). So I agree that as a general rule I'd use WiFi first, but there are enough exceptions that I'd not make a blanket statement.