If you attend a US University with a 141 school, you can gain a Restricted ATP with 1000 hours.
The R-ATP rule only benefitted a handful of large training ‘universities’ and as such they are very, very expensive with generally just a mediocre degree.
Some airlines will only recruit from one of only 11 flight schools.
That is not entirely truthful.
They may have flow agreements or ‘garanteed’ interviews with certify schools that use it for their marketing but they certainly don’t limit their hiring.