Not really sure how you can say this? There are tonnes of theme parks all around the country, small ones, big ones, nice ones.... that are perfect for that age group. There are plenty of beautiful zoos and aquariums coast to coast. There are water parks, great mini-golf, beaches, Great Wolf lodges etc... So, there is most definitely not a lack of alternatives. The only real thing Disney has going for it (as far as being an "option for tweens and younger"), is that it's "Disney" - it offers that storytelling connection, bringing the stories to life. That's what makes it stand out.
But I most definitely think that post-Covid, for those whose dollars are tight, where they might have considered going to Disney before, they'll now explore the many other more affordable options instead.