Re: Brittle software?
I would say the current Google hegemony is worse than the abusive Microsoft monopoly of the 90s.
Back then, browser makers innovated, and hundreds of thousands of webmasters (remember them?) strove to keep up, trying their best to please their myriad customers.
Now, those "hundreds of thousands" are whittled down to maybe a dozen hosts that actually matter - Google, Facebook, Twitter, Amazon etc. - and everyone else is either insignificant or (in most cases) piggybacking on one of the big players. Independent webmasters - the kind of people who actively maintained and tested their own CSS and JS - are, if not quite dead yet, then certainly a dying breed.
And when the dominant player in web hosting is also, simultaneously, the number one browser maker... that's a far bigger concentration of power than Microsoft ever had.
What gives me hope is that - I remember in the 1990s we thought Microsoft's hold was unbreakable, then Google came and ate their lunch. Someone, somewhere, will do the same to Google one day.