I agree, very bad idea - especially for ETFs.
Snip:
The SEC wants mutual funds and some exchange-traded funds (ETFs) to hold at least 10% of highly liquid assets — meaning cash or an asset that can be readily converted to cash — to help manage heightened redemptions during times of economic stress.
It also wants to enforce swing pricing and a hard daily close of 4 p.m. Eastern Time for traders — two amendments that have boiled the blood of fund managers.
Swing pricing tweaks the net asset value (NAV) of a fund in line with trading activity so that sellers bear the costs of exiting the fund without diluting the shares of remaining investors.