It absolutely is being done by the other side. Assuming you’re describing the sides of Mossad, the CIA, the FSB, and the Guoanbu.

No. Those guys are too busy influencing the Republicans and other right wing parties in the west. Although, i wouldn't be surprised if they used similar tactics, like massive bot nets and online propaganda to discourage the rest of the political spectrum from voting for other options.

That said, I think you’re seriously underselling the impact of strikes, boycotts, and walk outs.

That's part of the democratic process. You can do that, and still vote for the lesser evil. Not because it's right to vote for them, but to minimize suffering and make sure democracy still functions. Even voting for a different party would be preferable over not voting at all, despite your broken election system. At least that would give a statistical indication what people want from the government.

Instead, you now got a government that is actively trying to undermine the election process, builds internment camps for immigrants, which might be extended to political opponents pretty soon, is actively supporting a bunch of nutjobs to take over half the middle east, strips the government from all its money, threatens its allies with military action, destroys what little social security and education you guys had left, and empowers a new generation of feudalists to take over whatever will be left of the US. If it doesn't Balkanize before that...

Meanwhile, your leftists are accusing everyone not supportive of their non-voting strategy to be "genociders", and act surprised as to why they're losing even more ground in the battle.