Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.
That’s similar to what I used to do but iOS 14 killed it.

My method was to long touch a message, tap More, then touch another message and, without lifting my finger, slide slightly right and then up or down. The result was the same as your process.

Not only does iOS 14 ruin this, Big Sur beta removes the easy ability to select multiple messages and delete them. You now have to use the Edit > Delete menu rather than a right-click > Delete or Backspace or Command-Delete.

I’m not sure why they ruined such basic functionality.
 
As with everything apple it seems that they continue to ruin the stuff that makes sense.
 
I'm actually kinda happy they removed this. I was constantly accidentally activating this, and had to cancel out before I would accidentally remove a message.

But, yes, giving an option to enable the two-finger selection tool would be a better solution and please more people for sure.
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.