Ugh...I mean it's actually impressive how you speak with such confidence on a topic you know nothing about with completely false information. I'd actually mute you, but I feel like someone has to counter your terrible information.
Flows aren't completely one sided, but they're also not 50/50. They definitely do favor the company more than the potential employee, but telling people they're gimmicks...is impressively thick. Two years ago when hiring was out of control it was hard for me to recommend Aviate to anyone. It was easier and quicker to get hired at United as a traditional interview, then doing the program. Now, things have slowed down drastically. I'm not going to give exact numbers, but last time I did interviews there were almost no traditional interviews, and only Aviate and UMPP. If United is the goal, I highly recommend looking at the program. If you leave the program to go elsewhere, you're only ineligible to be hired for one year. If you're making that move anyway, you're not expecting to be in a United flight deck in a year regardless.
Yes United can keep changing the goal posts, that's a negative to a flow program, and why they favor the company more than the potential employee. However, you need to put up with that if this is where you want to be. You're better putting up with the headaches of the program and then potentially leaving, vs. not getting here.
These programs are also not there to staff regionals. They are an extended low risk job interview for the airline. They allow an airline to create multiple gates and make sure that the employee can meet all of those requirements before really giving them the job.
To the OP: I highly recommend Raven interview prep between the two. James does a really good job over there, and I've used him for all my interviews.