Its not some weird secret conspiracy by the Democratic leadership. The GOP generally has a much easier job. They get what they want by preventing anything from getting done. It’s much harder to create than destroy. Yes it’s on Democrat officials to actually follow through on their platform when they have the ability, but we can’t give them 51% in a system that requires 60% and be surprised when we don’t get sweeping legislation passed.
That’s before you factor in how different the demographic makeup of the parties being so different. The Democratic coalition includes far left, progressives, and moderates across the political spectrum with very different ideas. Some good, some bad. Some honest civil servants, some corporate sell outs. The GOP is made up of people who simply disagree about how public they want to make their goals known, they all have the same evil vision and they will all sell out their country.