100K spend may not be enough depending on the lifestyle one chooses, but even in a VHCOL, 100K *spending* is A LOT. Is it an unreasonable amount? No, not if someone wants that lifestyle, but there's no convincing me it's not a luxurious lifestyle. Having the financial ability to live in a VHCOL area in a nice home *is* a luxury.
100k for a couple doesn't seem outrageous to me at all in a VHCOL especially if you have even one ongoing medical cost. I helped a friend work out a guess at their spending needs last month, so I have this handy:
health $2,000 expected, includes paying 2x prescriptions for spouse, will increase over time above inflation
housing $2,300 includes amortized maint and remodeling (wonders of 1940s construction), property taxes (17000/yr), increases but very slowly
food $1,600
misc bills $ 800 (utilities, internet, cellphone)
personal $ 500 ($250 a month each, clothes, etc.)
gifts $ 100 ($50 a month each)
car $ 400 (insurance, maintenance/service, wear and tear, amortized cost of car)
travel $ 500 (two-ish trips a year)
garden, etc. $ 50 (amortized over the year)
pets $ 150 (food, amortized medical)
8400/month. The top 3 items combined are 70% of the budget. Food is the only one of those where significant savings are possible. In total, that's $100k post-tax per year in a state that does not feature a lower capital gains rate and thus taxes are on top of that.
Is there fat there? Yeah. Of course. Depending on your expectations, probably a lot or a little. This is a couple who has been living on that level for 20+ years and maintaining a crazy savings rate while doing so, so they're not going to be thrilled to change and, basically, don't need to. But I also think that a lot of the budgets people post don't bother to include amortized intermittent expenses and basically just leave that stuff out (home maintenance is a big one, failure to budget for medical incidentals and prescriptions is another big one I've noticed people leaving out - "My budget plan for medical expenses is to just be healthy!" - easy to say when you're 25).