I suppose that Google going through that exercise would mean that they get market dominance on bot gathering data and anyone not using Chrome Headless would be unable to obtain freebie data. This could enable future features whatever that may be. readjusts hat One future feature could be auto-discovery of Google DNS and Google proxies in GCP so they can learn about new data sources through crowd-sourcing thus making their big-data sets more complete and their machine learning more powerful. Developers could block the proxies or compile them out but as we know most people are too lazy to do this and many won't care.
Another advantage would be that eventually the only bots abusing Google would be bots using their code and they would know how to detect and deal with as they would implement their own open source anti-bot modules in their web servers, load balancers, etc...
There are more obscure ideas but I am doffing the hat before the hat-wraiths sense it.