Internally, Google is not so different from an ecosystem of VC-funded startups. They try a lot of things. Some ideas work and others don't.
The alternative is to never ship new products out of fear of failure. Or, to indefinitely support everything, regardless of how tiny. Or, to wait so long to derisk a new product that they possibly miss out on a new market (I'm looking at you, HomePod).
At the end of the day, this strategy has worked out well for them, so why stop? For every failure like G+ or Allo, there's a success like Google Photos or Duo.
IMO if Google really wants to try out new things, they should make these things invite-only to find out if they are working and how users interact with it, or clearly mark them as 'beta' or something like that. Google has a huge fan base and the internet is full of people excited to try out new things. But if users clearly see "hey, this is kind of a beta product, I am just testing this out" there would be way less disappointment if the product shuts down after a while.
I might be biased but I think Amazon is like this.
Disclaimer - work in Alexa
For some definition of work. They're still mostly (~80-90%) an ad-driven company, after all these years.
Reality: after 2008, economy boomed, and advertising also did. Advertising, once you have the means, is easier to scale, and high margin. Google stopped relying on just owned and operated properties, and diversified into 3p properties to achieve even more scale
Most other businesses or business attempts require massive operations which google lacks
Even you ramp up non advertising revenue to a billion dollar, advertising will grow more just because it is already big.
One of these is unlike the other. The amount of money invested into the ultimately-failed G+ is mind-bogglingly immense.
Try looking at https://gcemetery.co/ and naming how many of those you even recognize and can describe without looking it up. Everyone just loves mentioning Reader, but except the new batch of G+ and Inbox, there hasn't been any significant product killed in a while.
Your list is missing some high profile products like Google Allo and Chromecast Audio.
News and weather is basically just merging with another app, reply moved into Android (I beta tested reply, and despite the app being gone I still have the features), Tez still exists as a part of pay, showtimes got rolled into normal search, tango was experimental and became arcore, google x very much is still around, glass never left beta as a consumer product and is still relevant as an enterprise product. Chrome frame has no reason to still exist, Quickoffice merged with Google docs, the Nexus line became pixel, noop was a 20% project, not an official google product.
When you remove the garbage, you end up with a company that deprecates a few things each year, most of which you've never heard of anyway.
chromecast's ux was always waaaaay to complicated to understand for non-tech people and audio is it's first casualty.
Allo is overhyped, from day 1.
I recognized and could explain more than half listed, but only cared about a couple (didn’t care about Reader).
I've never worked at Google, but it looks like shambles from the outside. Kind of reminds me of a younger Microsoft back when three teams would create three competitive solutions to the same problem (although to Microsoft's credit they still support most of those to this day).
Google really needs to decide what it wants to be, what direction they're going in, and work together. I'm guessing there's some perverse incentives at play for some of this (e.g. promotions/bonuses for new stuff, nothing for updates to existing products, or other "boring" work).