Write-ins are not universal. Each state has its own laws in regard to write-in votes. Texas, for instance, requires “official” write-in candidates to file up to 45 days before a general electoin. Only the official write-in candidate’s votes are tabulated in Texas. Just writing in anyone in a blank slot won’t work. Most in TX seem unsure of how to approach a write-in slot: it’s too intimidating for the meekly sheeple here.
Each state needs to find out what the rules are and get that information out asap.