In versions before PhpED 7.0, it was possible to place toolbars on the same row or column as the menubar (File, Edit, etc.). Now, toolbars can be on the same row/column as each other, but not the menubar.

Can this functionality please be restored? For very minimal toolbar users, it saves a good bit of screen space.

I had the same question almost a year ago when 7.0 came out. No response either. I also asked if the useless "Source/Preview" tabs at the bottom of the editor could be removed because they are of no use for me and many people, and take up a great deal of horizontal valuable space (at least one more line of code could be seen). I'm a fan of the minimalist (but functional and no-empty-spaces) layouts too, and this change was one of the great annoyances.
Just get used to it and get a bigger monitor... part of the progress you know.. .

if you switch to "os" or ".net" them, it will cut menu to its actual width.
With "vs2010" theme, menu takes whole the row and does not permit any other toolbars here.

Not true.
I don't know what special version you base your statement on, but no matter the theme, the menubar doesn't shrink to make room for other toolbars alongside.