Is it easier to get a good grade in a class with more or less people (see details)?

Let’s say that a school offers two sections of the same class. One section has 60 students. The other has 90 students. To simplify this, we will consider that the quality of education is the same for both (so we are not debating whether we want bigger or smaller classes here).

The school has a mandatory curve as follows: 20% will get an A, 30% will get a B, 50% will get C or below.

Which class is it easier to get an A in, the bigger one or the smaller one, taking into consideration the curve? I assume that I do not know how I stack up against my classmates.

Argument for the bigger class
.2*90=18
.2*60=12
More people get an A in the big class.

Argument for the smaller class
.8*90=72
.8*60=48
Fewer people get something other than an A in the small class.

Argument for they’re the same
The same proportion of students get an A in either class (20%).

I think this makes the most sense but there is a big issue:
Competition
Let’s say that there are 15 smart people in the class. The rest are mediocre. All 15 would presumably get As in the big class while only 12 of the 15 would get As in the small class. Doesn’t it seem like then, that the big class is better?

On the flip side, lets say you got 50 mediocre people in the class. In the big class, all 50 would get something other than an A. In the small class, though, only 48 would get something other than an A. The remaining two would, through luck or hard work or both, get an A. Wouldn’t then, the smaller class be better?