No, protests could (and should) have happened earlier. They also have.
The No Kings protests occurred but caused little social changes. Given that the US doesn't have the same social support system of other countries, it is difficult for most people to protest for an extended time without essentially destroying their own life.
Due to rampant racism, the Black Lives Matter protests simply resulted in most white people taking personal offense instead of actually comprehending the systematic bias US society has against blacks and minorities.
Occupy Wallstreet lasted pretty long, but was co-opted by fringe social movement groups and homeless plants by police. And that happened during the presidency of everyone's favorite Dep president darling, Obama.
My point is that protesting right now, during an election period, instead of just fucking voting doesn't make much sense given that US society has very clearly marched to this point with everyone aware.
Afterwards, when the system clearly doesn't work, and/if we are still fascist, sure let's fucking riot.
With regard to the "coward" comment. If you aren't in the US, you likely don't have the same social political, economic, or societal factors in place so you can't really judge.
Also, more crudely, if other countries had got off sucking US dick decades ago, it would have removed US soft power, wealth, and resources, and allowed internal social movements to have more weight. As example, we wouldn't be able to amass such a large military if other countries hadn't allowed the US to be their police. So, kindly fuck off and fix you own damn problems so we can do the same, though probably slower because of you cowardly enabling fucks.