It seems to be
fairly well established at this point that poor ventilation is an issue; spending time around others who may be carrying the virus is an issue; wearing a mask, whether inside or outside, significantly reduces the chance of spreading the virus if you're a carrier. So your guess seems pretty on point. Indoor dining/drinking means being around others without masks in areas where air is circulated rather than fully exchanged, so it's about as risky as you can get short of a church service or choir practice (which has all of those risks but adds "let's project particles from deep in our lungs while singing"). "Spreading events" under those conditions have been pretty well-documented, as far as I know.
So, I'd say Dr. Morrow is aware that some of the restricted business activities drive transmission and he's supporting those restrictions. There are other activities -- like outdoor dining, as long as you're not putting diners in circulation-restricting tents -- that seem to be lower risk, and could probably further mitigate risks by having limitations on group size, dining time, etc., rather than just a point-blank ban. And there are some other restrictions which just seem more like theatre, such as curfews. Do we think coronavirus is nocturnal?
> Should we ignore them, then?
I'm not sure how useful that question is for folks who don't run businesses facing that decision. If I was a restaurant operator, I wouldn't flagrantly flout the local regulations even if I disagreed with them. I'm not, though, and the restrictions that more directly apply to me as a citizen -- e.g., try to stay at home during this surge, don't gather in groups even with folks in your "quarantine bubble" -- don't seem that wildly unreasonable.