well if Hive price is 1 cent or below are you saying the witnesses should not be concerned at all?

Yes, it is not their job to be concerned about price. It is every stakeholders job to be concerned about price. They should not be concerned about price in their capacity as witnesses but as stakeholders.

Less reward value might be a concern for a witness validating blocks and noone active on chain?

Refer to previous answer, suppose they are concerned about the witness reward they are receiving, they can shut down their node and be replaced by someone else. But as you can see that is not a concern for witnesses in general. If they don't value it in dollar terms, but just Hive terms. Changes in prices has no bearing in their reward. And blocks will continue to be produced even without no one active on chain. Once again that doesn't concern witnesses in their capacity as witnesses.

Surely there should be some element of responsibility even if their sole job is to secure the chain ?

What element of responsibility? They are not responsible for price, stakeholders are responsible for price.

All the things you are complaining about are stakeholder problems, not witness problems. Some of the top20 witnesses are big stakeholders, some of them hold 2-3x the power I control which is not that much. But things you list are not their responsibility in their capacity as a witness, but as a stakeholder.

For the things you list, someone that hold a few million HP but not in top20 witness will have the same responsibility with someone that hold that much hp and in top20 witness. Someone that doesn't have as much HP but in top20 witness will not have as much responsibility as someone holding a few million HP but not in top20 witness.