Hi @Doslobo
Microsoft recommends avoiding the use of Phone / SMS based authentication due to Security concerns as detailed by Microsoft CVP Alex Simons on this community post - https://techcommunity.microsoft.com/t5/microsoft-entra-azure-ad-blog/it-s-time-to-hang-up-on-phone-transports-for-authentication/ba-p/1751752
As an alternative for customers that prefer not to use the Authenticator App, FIDO2 and OATH hardware tokens are great options when it comes to a secure authentication method without the need of a personal device.
That being said, there's no official information about Microsoft disabling SMS. We strongly recommend you using the alternatives above, but as of now, SMS is available for all the customers as a Multifactor Authentication option.
Thanks.