The more likely issue is reducing the amount that can be put in the 401K and IRA but not the MyRa, which invests in government bonds.
A likely “solution” is the feds saying that to avoid uncertain market returns, X% of IRAs and 401Ks must be invested in government bonds. The percentage starts at 1% or 2% before ratcheting up.
I suppose I could google MyRa, but since you brought it up and I’ve never heard of one, would you consider a short explanation?