A body of web standards that they lobbied for and to be in the form that they are...
As an example, Google holds 18 of 39 seats on the Web Assembly Working Group. This means that if they whip their seats, they only need 2 additional votes to pass anything.
The first step in saving the web needs to be to stop adding so many new standards that are only needed for "apps".
That's making big assumption: that decisions are made by votes, and those votes are done purely based on participation.
And they're not. For decisions within the WG, they're normally done by some notion of rough-consensus (frequently, lack of significant dissent); actual votes within most WGs are relatively rare.
For decisions at the W3C level, it is admittedly done by votes, but it's one-Member, one-vote, so in that case all W3C Member are equivalent in power: Google, Apple, Microsoft, Mozilla all have their votes count as one.
This is pretty normal within industrial standards development organisations: voting happens at an organisational level, representing the industrial members, not based on individuals participating from those members. (There certainly are negatives associated with a disproportionate number being from a single organisation, but that's mostly related to disputes in meetings ending up with one individual arguing against ten.)