It's not the fault of the electoral system. It's the fault of the electorate.

No, it really is the fault of the system.

If a third party becomes competitive, then the odds are nobody breaks 270 electoral votes, and the House of Representatives picks the next President.

If a third party isn't competitive, then they just act as a spoiler for whoever major party they steal more votes from.

Neither circumstance is desirable, which is why the electorate is making the correct risk-reward analysis regarding issues that matter to them, and continue to vote for a major party that aligns closest to their views.

The solution to that problem isn't just voting third party. The solution is to basically do what the Tea Party did -- stellar grassroots organization to completely capture a major party from within. Of course once you do capture the major party, you don't use it to ram theocratic bullshit down everyone's throats, but instead to overhaul the electoral system so that hostile party takeovers aren't necessary to enact meaningful change in the country.