With term sheets the way they are with liquidity preferences if I as a VC invest $100 million in a startup for a 10% stake at a 1X liquidity pref, the valuation I'm placing on that startup is $100 million and that is therefore what its reported valuation should be.
No need for any repricing of these startups - just report their true valuation as largest amount invested with liquidity preferences.
Edit: Just an additional point to add - If I really valued it at $1 billion I wouldn't need the liquidity preference.