Most of that post was bad, but you got this part right: "Republicans and conservatives refused to coalesce around one of them and defeat Trump".  

I blame the RNC for a lot of that.  Having 17 candidates in the field, and for as long as they did, is ridiculous.  It dilutes the votes so badly that a mere 20-25% supports puts one in the lead.  Holding debates with 10 on the stage (let alone a 2nd debate with the remaining 5-6) was a recipe for disaster. The RNC needed to do way more to narrow the field much faster so consolidation onto a moderate candidate (which usually happens) could have taken place. It's the same problem CO R's had in the US Senate race. Glenn won the nomination with a mere 37%. We need instant-runoff voting. Graham likely would have won the nomination, and probably about a 55% chance of winning the Senate seat.