"It is not a secret that one of methods to unleash value in a stock is to split the company"
Yes, and it's not a secret that the other way to unleash value is to merge companies. See for example AT&T or Exxon & Mobil.
Yes, and it's not a secret that the other way to unleash value is to merge companies. See for example AT&T or Exxon & Mobil.
The same does not seem to be true for any of the Alphabet companies, except in the sense of being able to leverage shared user data for better targeted ads. Perhaps that does make it worth it to remain one company, but it's debatable, especially for something like Waymo which likely won't benefit from having access to search data.
This goes all the way back to the most basic theories of organization - why do companies even exist? Why is everyone not effectively a contractor? Why do companies not outsource every non-core function? And there are good reasons why companies exist - see https://en.wikipedia.org/wiki/Theory_of_the_firm External transaction costs are real and breaking Google up could significantly increase those.
Someone from Siemens once told me "Siemens is an investment bank that happens to own all of the companies it has invested in." I'm not sure whether that's true or not, but it's a good description of conglomerates in general.
All conglomerates are like this, the clearest example is Berkshire Hathaway.
Maybe you could ask from the opposite perspective, why aren't all mutual funds organized like BRK?
Others might say a better justification was the cheap corporate credit available to some (but not all) firms, and thus the competitive advantage of conglomerates was access to credit, rather than management. The smaller firms and individuals did not have the same access to credit.
But in the 80s, the pendulum began to swing the other way. The problem from the perspective of the credit markets -- whether shareholders or bondholders -- was the difficulty in obtaining detailed operational information from these large conglomerates. They became very opaque, as they could use the losses of one firm to subsidize another, and it was hard to drill down and figure out what was happening by looking at the financial statements. So then began a wave of slicing these companies up and selling off the pieces.
Or from a completely different perspective, it was the extension of new types of credit such as junk bonds that allowed insiders to do leveraged buyouts, which tipped the scales away from the conglomerates and led to a lot of asset sales that "unlocked value" while other operations were shutdown.
Not saying who is right, just offering some perspective that these arguments have been engaged with 60 years ago, and ended up with mixed results.