To put it in domestic terms:
* [January 1st] "Honey, I want to rent a Ferrari, I did the math and it fits if it's just one month! Pleeeeeease?"
* [February 1st] "Oh, that? It's the Ferrari rental-fee for the next month, don't worry, it's an existing expense, it's already part of our regular budget, so clearly we've proven we can afford it. We'll just have to cut back on insulin for the kids."
[0] https://www.americanprogress.org/article/senate-republicans-...
In politics it may seem like a good idea to create these time bombs because they can't imagine them going off but sometimes they do and here we are. The pied-piper strategy with the basket of deplorables was supposed to make it easier for Hillary to win 2016 but she didn't so we got the bomb going off instead.
You need a 60% vote or you need to take away someone else’s pie. Medicaid/medicare/social security are current contenders based on Republican planning.
The bigger issue is Republican voting districts gain less from putting it back in place. Most software devs are on the coasts and Denver.
The 174 changes (and SALT changes, and some other stuff) were how TCJA got balanced and passed without a 60% majority. 50%+1 is enough to undo previously passed legislation that was also passed with 50%+1 in this case (handwaving - not exactly right, because the balancing point is a different time range, so the math might not work out exactly the same).
The Democratic party absolutely could have passed some legislation in 2021-2023 to undo a lot of TCJA with just a 50%+1 vote, if they cut other stuff to balance. They didn't do that though. In part because they had literally 50%+1 majority and couldn't lose a single vote in the Senate, and couldn't come to an internal agreement.