Yea - but the majority of Americans want a policy like what Sanders was offering (Medicare for All) and neither major political party is on board with it - that's sort of par for the course of how US policy decisions look like - generally the US has gone with policies that don't actually gain majority support instead favoring the will of special interest groups.

Yes. Change is slow.

Also it's not like those old farts in the congressional seats lift their pens to write laws. They have a team of policy wonks that do that for them. They just present it in the respective chambers to play along with the charade. If you email your senator directly, it's going to be a staffer that fields the email, addresses your concerns, types up a response, and signs the senator's name in the signature.

Anyone who has lived on the Hill for any amount of time know what really makes this country churn, and it isn't the public faces.