Very interesting. However, not to nitpick, I wouldn't say "high end secular suburbs" were a "key part of Obama's base" ... firstly, he didn't pull ANYWHERE near the margins in those areas as he did in inner-cities or college towns, and the latter far outnumber the former in terms of votes.
Well not to nit pick, but that depends on how you define "base".
If you define it as smallest coherent majority you can win a primary with and whose turnout impacts a general election, but other than that has limtied impact, yes.
But if you take a more expansive definition to include a group big enough to materially swing an election like WWC votes for Trump, then no. Obama did rather well many of those areas like the Philly Burbs, So-Cal, Denver suburbs and so on.