Correction: After more research I learned that to some degree the jury is still out whether we can attain herd immunity to covid

 Here's the thing. As the Virus mutates further and further it might go beyond a place where it can infect people. There's a very narrow window where it can infect people and if it mutates beyond a certain point it can't. So, it could also be like the 1918 Spanish flu and go through it's mutations and variants and become endemic like that one did with herd immunity. The 1918 Spanish flu still exists here on earth but most people have now herd immunity to it. So, theoretically this could also happen by 2022 to 2024 with Covid-19 as well. But, no one knows for sure yet.

So, it's possible herd immunity might or might not be reached depending upon what the Covid Variants do next here on earth. It could theoretically go either way.