Create Channel with SysMes = false

Is there any way to create a channel via Rest API without system messages?

If I send readOnly = true then { “ro”: true, “sysMes”: false }
If I send readOnly = false then { “ro”: false, “sysMes”: true }

Is it possible to create a discussion with { “ro”: false, “sysMes”: false }?
Or at least to modify it to set sysMes?