It could be easily changed to.match but I am not so sure it is needed. In one case they are a toolbar and.in the other they are submit buttons on a form. So to me they are not the same thing so do not have to be consistent but I see no reason to prevent a change either

Technically, they're the same, just in different places.
I can do a PR to reverse it but I'm not an UX guy and thus assumed there was a reason :)

Pinging @andrepereiradasilva since it looks like this was done with #11830 (and related ones)

I guess no special reason at looking at the original pr.
I also see no reason to change that as toolbar and modals are quite different things.

@Bakual you are very very unlikely to get a reply from @andrepereiradasilva

Looks like

For what it's worth: in the mobile era the dominant buttons tend to lay on the right hand of the screen (easily accessed using one hand), but then again people in the community still believe that the admin area is not for mobiles...

And that assumes everyone is right handed. It's certainly not easier if you are left handed

The admin area can be used with mobiles, but more often it is used on desktops. That's not only a believe.
I'm not saying it's wrong that it is on the right side. I just found it a bit confusing as the order is different in that new modal compared to a regular form ("old" modals had them left like the toolbar).

I am closing this based on the lack of any overwhelming reason to change it.