No for the Clerk, who does not have any delegated decision making powers and no for the chair where regular scheduled meetings are concerned.
However, the Chair has the right to unilaterally call an extraordinary meeting or extraordinary general meeting, so in theory he/she could set up an online meeting under the revised 2020 regulations. This could apply to two other councillors as well.
That said, a significant number of cllrs could refuse to attend on the basis they don't have the appropriate technology to participate, and potentially make the meeting non quorate.