Not monarchy, but the 7 ultra-high tax states do suffer from one-party rule.
Many high tax states are depopulating relative to the more fiscally prudent states. This trend will continue in any case. Elimination of the tax deduction for state/local taxes would just accelerate the trend.
(I'm skeptical that elimination of deductions will actually happen.)
The cap on state taxes could have a serious effect on the price of real estate here in NH. This is because NH does not have a income OR sales tax. Instead we have very high property taxes. For example, the local property taxes on my single family residence is $8K. This is for a house that is currently worth about $340K. I know many upper middle class people whose property taxes are in excess of $10K here in NH. However, NH continues to be one of the lowest overall tax burden states in the country.
But this isn't 1986, and this isn't the Reagan tax cut. The two situations are different now. The GOP leadership is saying that once corporations get more money back, they will pass that on in higher wages and benefits for workers. I have my doubts.
There was a Freeper here who had vast experience with mergers, taxation, and businesses. He stated that what he saw was once corporations started to see more profit growth, they hired "consultants" that informed them they could fire xx workers, and cut xx benefits, and make even more profit.
If the GOP is counting on "growth", then screwing over states that are carry the largest share of economic activity and Federal revenue (NY, CA, NJ, IL, TX, etc) is not a good strategy. You say people will move out. True, and they have. But that won't immediately translate to growth in other states, nor in the Federal coffers.
“A democracy cannot exist as a permanent form of government. It can only exist until the majority discovers it can vote itself largess out of the public treasury.”