Nah. Except that the only thing that worries me is a big backlash on sales, unlike New Leaf and Wild World. (Where multiple towns could be possible on one 3DS) You can't with this.
it might make a teensy dent in sales, but nothing major. the switch is a big console and this is a blockbuster game so it'll obviously sell well, and a small percentage of people who bought new leaf bought a second or third copy. yes, we see them often on this forum, but this is still such a small percentage of us.