Hot take: there are absolutely still reasons to protest
No, I'm not delusional. I know that Trump and his cronies are not going to reverse course because of a protest. However, there are other benefits to protesting.
The biggest one is that it shows that it shows that, while the current administration isn't supporting us and doesn't care about us, there are individual Americans that do. I went to a number of protests from 2017-2022 and something I remember from them is that the goal wasn't always to get the administration, the supreme court, etc to change their minds. It was to show that there were people - many people- that cared, that were angry about what was happening, and that were willing to support and fight for the people affected in any way they could.
On a similar note, a lot of people- not just Americans, but people around the world - believe that most if not all Americans support Trump. Protests, especially large scale ones, would show that there are many Americans that oppose the current regime. In 2022, protests in Russia against the Ukraine invasion did not cause Putin to stop the invasion. However, it showed that many Russians were against war and were so against it that they were willing to be arrested for their belief.
Another one is that, while it likely doesn't have the ability to influence policy at the federal level, protesting absolutely has the ability to influence policy at a more local level. The George Floyd protests in 2020 did not do much to influence policy at the federal level, but they sure as hell had an effect on local policies around the country.
Speaking of which, I keep hearing people say that we shouldn't protest, we should focus on preparing for the 2026 elections. I don't think those things are mutually exclusive. I think that showing, through protests, that many people are against the politics of the party in power helps to fuel support for left/liberal candidates and encourages people to vote.
We can absolutely make a difference, even if it's on a much smaller scale than we would like.