What is the justification behind the limitatio…

What is the justification behind the limitation for swimming beasts for druid?

what is the justification behind the limitation for swimming beasts for druid? (need to be level 4 to wildshape into one) Would you do it differently today? Wild Shape isn’t meant to be the solve-every-exploration-problem-at-2nd-level ability. The druid grows into the possibilities. Working as intended. — Jeremy Crawford (@JeremyECrawford) May 24, 2018