This requires a bit of analysis. Reasons like this may influence individuals, but it's not likely to have an effect en masse.

Consider the basest implicit assertion a liberal has in their head. The state of affairs, which happens to be the capitalist model, is natural. This paints how they view history as well, but that's a different topic. Suffice it to say, history is over, and the best that can be done now is incrementally getting better until some ideal system, at which point we're the federation from Star Trek.

Imagine that mindset, if this is the system, is it not natural to seek improvement, even the slowest, most incremental kind? You may realise this is horseshit, that even in the short term their differences are practically random noise, but that realisation requires breaking from that initial assertion. How can a system be viable, let alone good, if it trends towards two choices that are equally terrible? Well, as it turns out the trend towards monopolisation usn't limited to capital ownership when capital looms over society.

You'd think, Obamacare and Romneycare being the same thing, or democrats not fighting to fill the SC, or Biden doing fuckall to fight so-called red states passing anti-LGBTQ, anti-women laws etc. You'd think being fooled by basically the same lie that's incredible to begin with and turns out to be a lie remarkably quickly would inspire some sense of credulity. Lack of analysis tools means this information doesn't register as it should and capitalist media ensures the information doesn't remain in memory long enough to recognise a pattern.

If the fatal contradictions of system of governance fall in a forest, and the only people who hear it are dirty commies, is there even a contradiction?