I am not aware of any significant change in minimum payment guidelines issued by the Feds since 2003. The guidelines were broadly phrased basically requiring that a borrower would have to be able to pay down their debts in a reasonable period of time. Most of the FCRA changes since the latest recession generally dealt with areas other than minimum payments (other than requiring lenders to let you know how long your payoff will take with minimum payments and allocating all payments beyond the minimum payment to the highest APR balances first).
Most lenders generally set minimum payments at a few tiers: 1) Minimum amount that is often $25 but ranges from $10-35 fairly often; 2) A percentage payment if over the minimum amount - often 2%, though sometimes different; and 3) A lower percentage payment plus interest and fees if greater than options 1 and 2 - often 1% plus interest and fees. While this is not always the case, most lenders have a minimum payment model that is roughly structured this way.
I think (not sure) that some law was discussed or went into effect some years ago to limit how much an issuer could raise minimum payments. Not sure if it actually went into effect, but the law's purpose was to combat issuers like Chase potentially raising minimum payments to 5% of the balance. Chase eventually did not follow through with the change to those with existing debt and I think the legislation fell through.
Disclaimer: Basing some of my answer on what I have read and heard over the years. While I am confident about certain aspects, I am less sure about others. The third paragraph above might not be accurate. I did read some articles about the topic and reviewed some of the proposed legislation, but that was about 5 years ago.
