Sounds like there isn’t a consensus according to your own statement.

Waymo is running on public roads right now without 5G.

IMO: if 5G is required for an “autonomous” car it can’t qualify as L5. That’s a remote controlled car not an autonomous car...

It would be crazy to build a car that won't work unless you have a 5G connection.

5G, if it is really the umbrella term for ubiquitous unlimited gigabit internet access anywhere, any corner on earth, then it might be useful to self-driving vehicle, since they can download the high precision maps quickly anywhere they go.

But that is it. First of all, 5G couldn't possible live up its claim, consider the number of stations that are required and how densely they need to be placed next to each other, it only makes economical sense to deploy them to populous cities.

But most importantly, L5 driving needs to tackle its 'brain' problem, that is a highly intelligent core device to schedule the vehicle's actions regardless of weather/light/road condition/erroneous situation where accidents occurs, to name just a few, and makes sure the driver and passengers alike, are safe. I didn't see how this could happen any time soon, not to even mention the legal challenges it might be facing.