Mostly I get verified by services or receive OTP via email as I've been doing since 1997.
I can receive most texts just fine with Skype but some services will refuse to send a verification text to a VoIP number. I guess they look you up in some API and find you're VoIP or there is some flag when they send an SMS that prevents sending to a VoIP IP. I can understand quite well that they don't want to deal with people who create large numbers of smurf accounts about I have had my Skype number for ten years or so.
As an aside I'll note: (1) it's a disappointment to me that Skype doesn't have competition as a consumer-oriented VoIP provider as Skype has its share of enshittification problems like the messages from pig butchering scammers, an attempt to spam me with news about Donald Trump and such, etc. (2) My son does have an AT&T phone which can allegedly call and text over WiFi. It works sometimes but is nowhere near as reliable as Skype.
