The problem being that daycare in the US is a train wreck. There just flat out aren't enough people willing to do it anymore. I have freinds that have kids, and they have to fight to get their kids into any daycare facility because there aren't enough to go around. Very few people are willing to do it now, because its a lot of work, with a lot of training, and all it takes is one angry parent to throw all your training and schooling into the trash and light it on fire. So facilities can pick and choose who they take in, because nobody can really tell them otherwise. Sadly it's currently a lose/lose situation for a lot of people. Long gone are the days where the neighborhood grandmotherly type or the family friend could watch everyones kids, as now that will 100% get the city, county, and state on their asses in a heartbeat for a number of reasons.
In the end, it comes down less to money, and more to parents. Even spending a few minutes a day with your kids reading with them, or even watching something educational instead of the usual PBS or youtube trash, makes a world of difference.
The pay for daycare workers is absolute trash and the expectations are way higher than the pay warrants..
It is still a money thing though.
Let me drop an anecdote here to illustrate my point. My kid is formally tested as profoundly gifted, 99.9+%, member of high iq societies, etc. So, not a dummy. My wife and I spent a ton of time on academic pursuits - math, reading, writing, etc. Additionally, like I said, 3x/week we had a 1 on 1 nanny situation taking him to museums, aquariums, kiddie plays, etc. So, not parents who were neglectful of educational enrichment. However, when we went to apply to pre-k (a fancy private school option) we learned that he was behind expectations on certain things. How? Because the school expected him to have been taught certain things. And since we were educating how we saw fit, we had missed those specific things.
It didn't affect his ability to get in (he could read since he was 3 y.o., do complex math for his age, a solid chess player from 4 years old, just absurdly smart in a way that's impossible to miss). But, technically, he was behind the other kids. At his ability level, we bridged that gap in a week or two. But not everyone has a kid of similar ability nor the time to devote to those things - assuming someone even bothers to tell them.
So, when people say "just spend time on educational stuff" it's misleading because the educational stuff is a very broad subject and most parents have no idea what the expectations are for kindergarten or 1st grade. So they might be doing the education thing and still coming up short. That's where the quality daycares and similar facilities make a difference.