It's annoying but it's still there: more or less.
If you go in the view menu you'll find the 'sort by' command is still there. You can still sort by 'From'.
But, yes it's hidden in the menu now.
And they have now introduced the 'favourites bar'. Well, I never saw it before but it was probably there.
It's near the bottom of the view menu to enable it.
You may have to define your senders as VIPs for instance to be able to filter by a sender that way
You drag a mailbox etc into it add it.
Also if you look for the 'customise toolbar' command in the view menu, you can get some more options there.
I didn't realise for instance that the 'unread' and 'read' icons toggle. I don't remember that happening before (that is they toggle one or the other then don't toggle on or off by clicking on just one of them which is usually the way these things work and what caught me out).
I don't see anything better the way it is now. Mail works ok but still is slower than Spark for instance and I do find it much more difficult to find things I'm looking for.
Best