Of course masks had some practical use. I am only talking about their current mass use for this covid lie. The evidence that this kind of use is unhealthy is quite strong.
Symbols used in worship become part of that worship. This is why the Israelites were required to get rid of symbols of other religions in their places of worship.
The mask symbolizes censorship by covering the mouth. And it symbolizes the general loss of freedom because it is based on mandates.
Symbols mandated by bad people are bad. Leviticus 19:27-28 is all about avoiding such symbols.