Agreed. It is so bad that it MUST have been deliberately designed to be so.
A trawl through the interface would suggest that only a few hundred films were available. However, if you know the title there are many many more available.
There is no way to discover films from specific film studios (a good way to look for specialist and art house films). There is no way to discover films in a specific language.
There is no way to search films by decade.
.....
And the limit of 16 genres is truly appalling and lists seem to be limited to 100 max.
Again, it's so bad it must have been deliberately designed that way so as to focus your purchases onto those they want you to buy.