BTW that is filibuster proof if using their remaining budget reconciliation passage for this (a hack, but it seems hacks are how everything gets done).
There's only 100 senators, and of those senators, the majority is just "50" (because the vice president is a tie breaker), and in that majority, at least one senator, if not two, live in heavily red states and don't always agree with their democratic colleagues. But, even barring that, the filibuster rules make it difficult to pass anything, even with a majority, because you actually need enough votes for a cloture vote to stop debate.
Technically speaking yes, we could just pass legislation at the federal level to solve a lot of issues. Practically speaking, passing legislation at the federal level has been a complete challenge for both parties in recent times. When Trump was president, a coordinated effort called SwingLeft systematically secured a majority in the House specifically to win legislative control, for example. It is likely that in the next election cycle, a similar effort will occur due to redistricting, which will likely give the house to the republican party, thus making legislation equally difficult (because the president is a democrat, congress will be republican or deadlocked). If you go back far enough, this is the type of thing that stymied Obama. I don't know if it happened with Bush, but it's relatively easy to, for lack of a better term, deadlock congress because of its unique election rules and vote distributions.
Were it so easy.
I do see that it could just swing back if things change.