It still would slow down a bank run, and Coinbase conveniently/suspiciously going down when bank runs seem to start would further cut off impulse selling - and

It still would slow down a bank run, and Coinbase conveniently/suspiciously going down when bank runs seem to start would further cut off impulse selling - and arguably long enough for manipulation to happen elsewhere to turn price into upward trend again to quell impulse selling by potentially artificially making the price look like it's rebounding.