Earlier quoted context omitted.
Fiber is the hint about what this really means. Capital intense businesses like ISPs or car companies are expensive to operate and the financials would drag down Google. In this model, the big shareholders get to dilute risks in these ventures, while retaining the ability to exponentially increase their personal wealth.
This reorganization makes no difference on the financials. The release explicitly stated the company is trading at the conglomerate level.
Going forward, this re-organization may very well allow capital allocation to be done at various legal entities a-la project or structured finance. That way, the risk/return of the various projects can be traded on more efficiently to the benefit of both investors and google/alphabet shareholders.
This is relevant in the larger context for asset intensive, long-time maturity investment areas --like fiber, self driving cars, etc -- that have fundamentally different economics than the core business (search/ads/youtube etc).