@Bob *********
I say NO, only option for on-line work without Thai clients is
purpose workcation (Digital Nomad/Remote Worker/Foreign Talent/Free lancers, BUT that is the official wording of the Thai Minsitry of Foreign Affairs who as you know have no clue about Thai visa regulations.
OR as DTV specialists say, foreigners must provide print out of the Thai law in English, certified by lawyers, DTV holders, foreign ministries and who know others to be believed as true.