> technique should only be used for major felonies

Doesn’t the crime they were pursuing, dealing heroin in connection with an overdose, rise to that level? (No comment on the merits of the law. Just the facts of the investigation.)

> if you want to commit major felonies

That's not how it works. Sometimes the police suspect people who are innocent, and they work hard to get them on technicalities if need be, and meanwhile, the risk of inadvertently and unintentionally committing obscure crimes is substantially higher than zero, so...

Or rather, please do.

This one has been the case for years. Even when the technical capabilities were only at theoretical level, any criminal with some brain used to switch off their phones+ take out batteries before even having any discussions, not to mention commiting crimes. Today's phones can't be used anywhere in any context if people are involved in some criminal activities.