You have the right to peacefully assemble. That is a fundamental right. Good people have suffered and died for it. And yes, some crazy people ask us to listen to things we don’t want to hear. Nonetheless, your rights under the First Amendment cannot be repealed by executive order, local ordinance, state law, or act of Congress.
Yes, a government can make reasonable regulations of the “time, place, and manner” of public gatherings. That means, if you want to assemble a few thousand people in a park, you generally need a parade permit, but the city cannot charge you $20,000 as a permit fee just because city officials don’t like you. That means that you cannot march into the legislature in session and scream, though you can march in front of the entrances (without blocking them). In short, if you want to preach your religion or sing your politics in a public place, the powers that be cannot seriously hinder you without risking a civil rights lawsuit.
The First Amendment is for everyone. In fact, the most important First Amendment rulings have been in favor of many groups and causes which often faced considerable public opposition: communists, anarchists, neo-Nazis, Jehovah’s Witnesses, pacifists, anti-war protesters, Jews, Quakers, Catholics, Mormons, and dozens of Protestant sects, as well as flag burners. If this lockdown/stand in place/quarantine lasts much longer, you are going to see dozens of First Amendment lawsuits, and the local and state governments are going to lose (and have to pay the attorney fees of the winners).
Even if you believe that state and local governments should be able to place much of the population essentially on house arrest, as a taxpayer, you do not want to see your tax dollars being paid in the large sums to the attorneys who win civil rights lawsuits. Though it is true that any public assembly could potentially lead to a riot (or the spreading of communicable diseases), but we are a free country, and for 240 years we have considered the risk of a riot the welcome price for the freedoms of speech, religion, petition, and assembly.
Wherever there is an action, there is a reaction. Americans are not docile. If we were, we would have stayed at our old homes and not immigrated to our new home on these shores. I predict that the overreaches of the quarantine, originally called in March while Italy’s healthcare system was overwhelmed by the virus and apparently suffering from a death rate of ten percent, will gradually be lifted. “Consent of the governed” means that restrictions on personal liberty are lifted as a crisis passes (or gets old). If they aren’t, then we Americans are very good at ignoring laws we don’t like.