Age is a larger predictor of political party affiliation than location[1], and the CFR of covid-19 against age[2] means the deaths will disproportionately be republicans. Every elderly persons life is also worth more, on average, in terms of number of votes because the elderly vote more than the young[3].
An early end of self-isolation would be an unmitigated political disaster for the Republican party. These are statistics so simple that even politicians should be able to understand them.
Edit: I would also like to add that it is very early days for covid-19. A significant percentage of the population will be infected at some point before November. How high of a percentage is inversely related to how long people self-isolate. The states that are barely hit at all today will the "worst hit states" tomorrow.
