The Fed is backed into a corner. If they cut rates now, they are signaling that Trump's economy is weak. The rest of the world is already looking like it's about to enter a recession. That will spill over and impact earnings/PE expansion, etc.
How to imagine that we don't tip over into a recession sometime in 2020.
Doesnt it seem more likely that we are headed to $1500 vs. beyond $3000 long-term?
If you have the opportunity to read George Soros book "The Alchemy of Finance" I think it will greatly develop your game, it certainly did for me.
On a transitory basis your view would be correct, however, lower rates have facilitated corporate buybacks that have totaled $4trn since 2009 lows (equal to the Feds balance sheet). That is likely to be a driver.
The data is still suggesting we are expanding and should do so over the coming 6-12 months. $3,000 might be a stretch but I can see many circumstances in which the markets reach new highs.
Hope this helps.
I think buybacks will be a risk if near future, but that's personal speculation. A lot of political talk around it.