Yes, that is true, but it is also important to point out that people should do the math about their options before jumping at an off-brand points redemption. In general, an off-brand redemption gives a poor value exchange on your points when compared to an on-brand redemption. However, if you are unable to do an on-brand redemption then the points are effectively zero value to you, so getting WDW CGs is a win! However, that opens up the question of why get a credit card that gives you points you can’t directly use, when you could get another card with a similar intro deal that gives you points that you can more easily use?
Yes, this is also true. Sometimes it is difficult to get the comparable value for a given trip, so you have to decide whether it is “worth it”. For example, for a recent trip I got only 0.83 cents per mile for AA miles valued at 1.4 cents, but I had a ton of points and didn’t feel like forking over the cash. However, on the same trip I got 1.88 cents per point for Marriott points valued at 0.8 cents (with the strong likelihood of being upgraded to an even more expensive room), so I figure that overall I’m getting pretty good value!