Another option: Are some of these suburban voters right of center people who have a deep personal antipathy to Trump but would be fine with voting for most other Republicans? Examples of this type of person may be people like George W. Bush or the writer David French (neither have endorsed Biden but neither one is voting for Trump)?
Also, question I've had for a long time: When the media talks about Rockefeller Republican types, some of the recent blue state R governors, maybe Brian Fitzpatrick, etc. as "fiscally conservative, socially moderate," what is the difference between "socially moderate" and "socially liberal/progressive?" Why do people not use the latter?
I think there are more people like this than we think. People who abhor Trump's personality but like having low taxes and are skeptical of a Green New Deal/SJW culture.