In practice since 2008 even if the theory is that it’s up to 250k in practice banks get acquired from the FDIC basically on the unspoken condition that all deposits are maintained at 100 cents on the dollar
Its not “unspoken”, its the overt goal to find a bank to take over that will provide that.
But SVB is a much bigger bank with a much larger share of uninsured deposits than a typical bank failure. If the problem extends beyond liquidity and really is an insufficiency of assets by any significant share, its going to be hard for a no-loss takeover to be facilitated.