Maybe you'll convince me otherwise, but here are some thoughts...

For one, it's free to me (or pre-negotiated, however you want to think of it).

For two, as I understand them, it generally comes with better terms. [At DL, disability pays 50% of the highest 12 consecutive months in the last 36, with no offsets unless you exceed the 'original' 100% threshold (which is super unlikely/rare), and includes Profit Sharing and potential "retro" pay in the calculation. And, it continues to whatever the FAA mandated retirement is - so age 67 is already baked in (if it happens).] I had a buddy who had a huge year with the last contract's Retro pay and the following year's Profit Sharing being in the same 12 months. He actually got a pay raise on disability from what he had been making, lol. Not that it's typical, but still...

For (maybe) three, and I say this not actually knowing what other companies do... Being contractual and 'in house' at DL, we don't have an outside company* materially getting in the middle of it do deny or reduce benefits. Like how UHC makes health care a nightmare as a third party. *Harvey Watt does administer DL's disability program, but having used it twice, my experience was very simple and easy with them. They basically just validate your sickness, and send a 'thumbs up' back to the company - that's it.

For four, and I can't believe I'm saying this, but I trust DL to pay up more than I trust XYZ mutual to pay up. Or said another way, I trust XYZ less...

ALPA also has some optional disability insurances, which I do pay separately for, and came in very handy when I had a major event. But that's beyond the scope, I think?

Why do you think outside policy is better? Genuinely curious.