Bigger driver numbers have never been the reason for accidents in F1.I disagree when i watched in 90's there where 25 starters. But at the back there was a lack of talent. Less teams makes it harder to earn a seat or even pay for a seat. So drivers with less talent are less likely to get a drive. F1 is the pinnacle of motorsport. For that reason we need the best drivers in the world taking the seats. Or rich mediocre drivers paying their way in. More slower drivers at the back just filling up the grid will cause accidents and drama. There is enough congestion in F1 at the mid and back of the pack.
As to wanting the most talented in the sport... Look at the list of drivers currently without a seat in F1.
Look at those under threat of never getting back in due to too few teams
You've got talented guys like Sergio Perez...possibly on the way out for good.
As to back-markers....Alonso started in a Minardi... Vettel a Toro Rosso... Schumacher a Jordan for one race.
Those teams were vital for guys to 'hone' their driving skill by learning how to handle a difficult car.