While you wait for better answers, I would like to make a plea on behalf of UI consistency.
Tabs are popular with mobile designers for the same reason virtual workspaces are with window managers: they allow multiplexing of scarce screen real estate. I use i3, which probably leverages virtual workspaces more heavily than most other window managers out there. It would weird me out to no end if suddenly there was only one workspace that I could manually close, and even more so if attempting to close other workspaces instead diverted me to workspace #1.
That’s what I’m hearing when I read this:
That is not how tabs should behave. “Who are you to tell me how tabs should behave? It’s my app and I’ll decide how tabs behave”, you may be tempted to say.
I have lost track of the number of threads I have seen here from people who try to abuse tabs and then complain that they run into technical problems doing so.
Tabs should be like rooms in a house. I’m only in one room at a time, so the lights don’t have to be on in the rooms I’m not in, but it is not the rooms’ job to try to dictate which one of them I should be in, and when I leave a room and go back to it later (which I must be able to do freely), everything should be just as I left it.
As a bonus, when you do use tabs this way and only this way, you run into far fewer technical troubles with them.