Why do you specifically need SMS?

Edit: Am I to understand, you use Signal as a default messenger and need an application to communication with those who are not also Signal users?

Not the OP, but that's how I use Signal. It's my default SMS app on my Samsung phone.

I have my SMS history there going back multiple years from multiple phones.

I'm curious where others in similar situation are moving to.

Is splitting Signal and SMS into different apps a deal breaker for you? The post seemed to describe SMS messages defaulting to a preset application of the user's choosing on Android.

which application