It has always perplexed me why there is a desire to deal with kind of thing at the federal level in the first place. States being able to decide these things for themselves is supposed to be what makes such a massive country stay functional.
In so far as the federal government can unilaterally expand its reach, it will tend to do so, if just because being part of the federal government makes you more likely to think things should be regulated at the federal level. The authors of the Constitution knew this, and drafted it to safeguard the rights of state governments. But "states's rights" has been a dirty word for quite some time.