ESPN Unlimited is $30/month. If it is being added "at no cost" ie to the basic package, it is because YTTV basic package price will go up to cover that cost.Looks like it will.
Additionally, ESPN’s full lineup of sports – including content from the ESPN Unlimited app, launched earlier this year – will be made available to YouTube TV’s base plan subscribers at no additional cost by the end of 2026.
I saw an article in the last week or so that said ESPN Unlimited was the actual hold up on a deal. While the original reporting was that YTTV wanted a lower carriage rate, there was a subsequent agreement on the carriage rate, but ESPN/Disney wanted ESPN Ultimate added to the base YTTV package. If you think ESPN/Disney is giving ESPN Unlimited for free, then I have a bridge to sell you in Iowa. If you think Google is going to eat that additional carriage rate, I have a different bridge to sell you in Nebraska.