Not confident in this space, either, but it seems like the loan is the loophole. So maybe using an asset as collateral counts as realizing capital gains?
(And, yes, of course: establish a sensible annual exclusion, so no one accuses me of trying to demolish second mortgages for middle-class families, or whatever.)
What (good-faith) second-order drawbacks might this have? I'm genuinely curious about whether this would be a feasible idea.