But they're two completely different things, right? Let's put it this way. Let's say I want to invest a ton of time/effort (like a whole year's worth) learning ONE UI controls toolkit to augment my angular development. Given that, I should choose one or the other of these things, right? Either install @angular/material via the angular cli and work with that (and not use your MDB Angular Pro stuff), OR NOT install @angular/material via the angular cli, and instead install/learn/use your MDB Angular Pro stuff. Correct?

Both Angular Material and MDB Angular use material design rules as a guidelines for styling and offer ready to use component for creating user interfaces.

Despite of using the same design style, these components still vary in terms of appearance (and sometimes functionality as well).

You can read more about material design here: https://material.io/design/

And here is our documentation in which you can find examples of our components (use sidenav menu on the left to navigate):

https://mdbootstrap.com/docs/angular/