> you don't close them off in a way to deliberately cause a crash. Basic politeness.

Typically the rules of racing will say you don't block faster cars or deliberately drive dangerously, etc. e.g. Forumla 1 says:

https://www.formula1.com/en/championship/inside-f1/rules-reg...

But yes, this Roborace thing seems pointless unless the cars are made by different teams and have different software, etc.