The recent announcement by Google of a service to mitigate DOS attacks looks like a very definite benefit for small companies that don't have the resources they need in order to handle that kind of attack themselves. However, this is by no means a charitable offer - Google reaps very definite benefits from this, and becomes even more of a central figure to the modern web.
The way that the service is advertised to work is as a reverse proxy - the same basic business model that CloudFlare offers, where clients are able to take advantage of a larger, more widespread infrastructure in order to deliver their content more quickly and reliably to geographically-distributed customers. There are many content-delivery networks at various scales that offer similar services, though the largest ones (Akamai and L3) are more geared towards the largest corporations and biggest media producers.
Where this becomes especially notably useful for Google is in its ability to more effectively monitor the traffic going to certain sites. Given the increase in adblocking and the associated blocking of related tracking methods (which use the same basic mechanism), Google is undoubtedly concerned about their ability to deliver their core product to their core customers.
The product is, of course, you - and all the other people that Google tracks - and their core customers are the marketing and sales organizations that buy this tracking information in order to more easily grease the path from your wallet to their bank accounts.
By giving themselves a privileged network position, Google is able to more effectively count and track the visitors to these sites - and to do so in a way which cannot be blocked by adblocking software. If they are the gatekeepers, then they control who does and does not reach the content that they are proxying for - so you, the consumer, are forced to go through them and be counted and tracked accordingly.
True, other businesses in this sphere have that capability - but unlike Cloudflare, L3, and Akamai, Google's income is primarily in the business of advertising, rather than in the business of the services that they provide.
So while it looks like a net benefit for the news sites that agree to it - and, frankly, it is of a significant benefit to at least some of those organizations to be able to lean on a much larger infrastructural base to mitigate the kinds of censoring attacks that they are susceptible to - keep in mind that nothing comes for free, and the only reason that such a service is being offered is because it benefits Google significantly more.