I decided to look more into the Polygon bridge itself. This part, by itself, doesn't feel like a scam. They've essentially created a new token type (MATIC) which is used to represent each bridged currency, so it is bidirectional in a way.
What actually seems to happen is something more like this:
On the main chain, you create a MATIC token which encodes some amount of ETH and costs gas. When you want your money back, this MATIC token is cashed in for ETH and some gas is paid.
I'm looking more into how these tokens are organized to make cash-out part work on the main chain. As I'm conceptualizing it now there must be a locked in value for the amount of ETH that MATIC can represent.
We come here in search of a place to express our thoughts outside of the direct control and surveillance of unaccountable, mega-corporations. There is no common theme that binds us other than these being the bonds we've chosen rather than those that have been chosen for us.