Don't use zoom then?
Behold, I know, sometimes you do not have a choice to do so. But isn't it sad, that just for stable zoom calls you need to upgrade your Mac?
However, it is true that if you buy your Mac for heavy lifting (i.e. professional use as a sw developer or content producer), 8G doesn't cut it and on circumstances even 16G may not be enough (e.g. if you use virtual machines or docker containers a lot in your software development process)..