Let’s say you’re a mega wealthy billionaire who has suddenly realized that if he cozies up close to a presidential candidate, he could have more power and wealth than ever before. What’s stopping you from figuring out who the electorates are and offering them whatever they want if they vote for your guy? What’s stopping them from taking the deal?
If you attempted this you would find the majority of electors report it and you get arrested. Electors are the big party supporters and so most are not going to take a bribe. Well maybe you could get the Harris electors (who know they will lose anyway) to support a moderate Republican, but you won’t get any republicans to switch to this new candidate. The never Trump republicans who would thus be willing to switch their vote are not electors.