I actually liked not having tabs, I'm a little sad about this. It was nice to have something at least trying something different for once, instead of doing the exact same thing everyone else is doing.
I like different but in this case (I think) different wasn't better. I applaud them for trying and then seeing that it didn't work well so they fixed it. They also allow you to disable this feature if you don't like it :-)
"If you prefer not to use Tabs, you can disable them through the workbench.editor.showTabs setting."
You can disable them, but disabling them makes you the weird guy using the not well supported workflow. I'd much rather have it the default.