After reading a wsj article this morning about what happens when cap gains taxes are reduced it made me think this would benefit IB's trading volume.
Essentially, when cap gains taxes are lowered, naturally you'd have increased selling of long term holdings increasing trading volume plus bringing in more tax rev to the gov.
Longer term, one would think that there would be more churn in general. IG, if cap gains rates are zero, holding periods should shorten. Therefore, if rates go from say 20% to 15% or a 25% reduction in any related cases, there should be some degree of shortening of holding periods resulting in more trade volume sustain-ably, or as long as rates are held at the newly lowered rate.
Long term, I suppose there would be less total tax revenue generated, however, if you're Trump, likely thinking in 4 year time horizons, it's a no braina. You'd get more tax revenue and fulfill the lower tax promise championed by his side. Perhaps, you're buddies would be happy as well. Considering the other side left Trump with few levers to pull, they've been pulled already, it seems unlikely he would miss this opportunity to assuredly bring in more tax revenue while optically lowering tax rates. From what I can surmise, this will likely happen quite quickly.