The difference between winning and losing in the NFL is so fine that every team is looking for an edge, they all look at talent a little bit differently.
Some teams tend to focus on major winning schools with a lot of talent. They think of it from a standpoint that the players practiced against better players on a regular basis and learned to win at a higher level. Other teams focus on trying to find the "hidden gems" from teams that weren't as successfull or played at a lower level.
There are arguments for both sides. One side says you get better by playing and practicing at a much higher level. The other side says that you get carried by the talent level and never have to learn to step up. One side says that winners are winners, take the guys who know how to do that, the other side says in the NFL you won't have the easy games and nobody wins them all, who will stand up and play well through the good and the bad.
At the same time there are teams that focus more heavily on performance, what did the guy do in games, while others look at measurables, how big, fast, strong, etc. Some teams almost seem to have no clear, coherent plan jumping all over the place.
Bottom line is that the pros find talent everywhere. Some guys always get missed but that is much more likely due to bad evaluation than not being seen. Every team has a scouting staff and those guys have their networks of contacts to find players. Even if a school is a D2 or D3 school if they have a potential someone is going to tell one or more scouts and the scouts will follow up, if even just to confirm that the kid isn't that good after all.
The only time that going to the NFL should be a consideration for a kids college choice is either if a school has a particular position coach known for developing talent that the NFL likes or if a team runs a system that favors a players chances of going to the NFL (for example a lot of O-linemen from the pass heavy spread teams (run and shoot version) tend not to be able to run block the way the pros like and their pass blocking techniques aren't quite the same as well. They may still do okay based on talent but if they are marginal they may not adapt fast enough to stick. Other guys who are marginal in talent but go to a school running a good mix of pro style techniques may stick despite talent deficiencies because they can contribute right away.