I love hearing that at least some companies did that. Neither my nor DH's employer did, and our personal benefit from the adjusted tax tables wasn't enough to offset the other changes (BTW, that child tax credit expires at *16* - two of my three are no longer eligible, though they are full time students living at home). Our 401ks are doing well, but with 20 years to go until retirement that's so abstract as to be meaningless.
But the bigger problem with the tax cuts is that they added massively to the federal deficit. It isn't that the cuts themselves were bad; it is that the fact that we borrowed to pay for them will constrain future discussions about economic stimulus spending in the next recession. Historically, the deficit has had a cycle of its own, growing when the economy was weak and shrinking when the economy was strong. The tax cuts disrupted that and put our govt. at risk of not being able to invest in infrastructure, expand safety net programs, or otherwise provide a counter-influence when the economy slows down.