It might be easier for some to blame Trump for the GOP going the way of the Whigs.
Trump is just the RESULT of the GOP having made themselves irrelevant and becoming just the right arm of the Democrat/Marxist oligarchy running DC. The Ruling Class Establishment leadership killed the GOP after many years of treating their base like battered wives and telling us to suck it up and take it.
Trump is just there to bury the GOP for good.
It's well deserved I must say.