“Unfortunately, every Republican seems to have voted FOR doing so.”
IMHO a different situation. The dimoKKKRAT controlled Congress and Presidency went on a wild spending spree and put out country deeply into debt. The President is continuing to spend like a drunken sailor. They need to be reigned in and this is one step.
Somewhat different situation, but the same general motivation, I think.
The post 2000/post Bush's first election years were a low point for the Republicans - total control of the government, and they used it to enact stuff like the Medicare prescription drug plan, and other massive spending programs. Couple that with the wars, and we see GOPers in Congress who failed to prioritise which spending was really needed and which wasn't, leading to why we "needed" to raise the debt limit back then in the first place.
So yes, we're in a lot greater debt now, but the whole principle of "giving ourselves a higher credit limit whenever we want" was being established back then.