I haven't seen the film. (I can probably imagine what it's about).
"...How much harder it will be to get through to people..." Yes, you're probably right.
In order to "...let ONE slip through the net..." there has to be ONE to begin with.
Since for example when the TSA at airports in usa were "tested" by FBI, they managed to let 95%+ "slip through the net" it's a fairly safe bet that any that do "slip through the net" would likely be false flag type operations.
This "searching people" stuff is pure theatre and propaganda. (It seems to be effective on a high %age of people)
Now, like I said, education can be important if you can persuade people to look at evidence etc etc. but it's not just an information or problem. It's mostly a psychological problem.
As you are no doubt aware, it doesn't make much difference to lots of people how much evidence you show them, if that evidence challenges their world view etc.

This is why Larken's "Mirror" project looks pretty interesting.
Remember we don't have to persuade everyone that being free is a good idea. 10% or less is probably a good enough start.
A few yrs ago, you didn't have the knowledge you now have (I'm guessing). With some research, you began to realise what's going on. There are many more people out there, willing to do the same, given the chance.
Anyway, I think it's pretty cool that you seem concerned about it. Keep on Rockin'