Not that poster, but judging by what the largest protests in the US ever - the George Floyd protests - achieved when it comes to police violence in the US (it's the same or worse now), in the present age in the US merelly coming out and walking for a bit in your own time while holding a board up doesn't seem to achieve anything.
Think of it from the point of view of the Political and Money "elites" in the US: they get zero direct negative impact from the riff-raff in their own time doing a big march against the elite's puppet mango emperor, and there is no single Historical instance in the US were the lower classes rebelled against the upper classes and properly fucked them up, so the masses marching isn't even a warning of increasing risk for them - they control the entire political system in the US and make sure whomever is in a position to get elected for a position of political power is always in their pocket, and do not fear the desinfranchised population because they never ever moved against them.
The murder of the CEO of UnitedHealthcare by a single person seems to have achieved more in terms of scaring the powerful than even the millions that came out demonstrating against the police killing of George Floyd.
(I bet that in a place like France, still today the masses coming out even if doing nothing but marching and holding some boards, are cause for concern amongst the "elites")
I actually saw something quite similar in the UK when I lived there: the powerful just didn't care because even large numbers of people doing some polite marching did not damage the interest of the elites and because they had no reason to be concerned with their personal safety because the plebes had never actually rebelled against the upper classes.
That said this situation in the US is even less concerning for the elites because the crowds are so firmly focused in the puppet and disregarding the puppet masters, that even very indirectly there is zero risk for the true powers.
Maybe as some other poster suggested, a general strike would be more effective.