No it doesn't. You have a two party system which makes things much more complicated.

1. Corporate dems are payed by their donors to keep the left at bay, if they do it through policy while in power or through playing opposition doesn't matter that much.
2. As long as you have only two parties people have nowhere to go, there will not be enough pressure to change the party.
3. A low voter participation does not lead to systemic change, it leads to even less democracy overall
4. If you believe democrats would move to the left through less voters than the same would be true for republicans when we elect democrats.
5. You are not the majority, the voters show us again and again that they will not stand behind progressives in big enough numbers. This does not only go for the US but worldwide.
6. If you do not vote you still carry blame, Gaza might have looked the same but people wouldn't get shot in the street by ice. Governtment agencies wouldn't be reduced to a minimum and so on and so forth. There is real world harm done by republicans right now and if you go back Nixon and reagen did immense damage to the country to this day.

Its just not that easy if your activism is reduced to "not voting" than it is completely meaningless.

Hey, that doesn't actually work because they don't give a shit. You aren't "teaching the establishment a lesson" because they don't actually need your vote to enrich themselves. Meanwhile the Overton window steadily slides to the right.

But maybe when the opposition is trump you should avoid to abstain?

the only people browbeating leftists to vote for their preferred color of genocidal warmonger are right wing extremists posing as leftists.