It is a meaningless website. Everybody and their dog knows that in the present political climate it’s practically impossible to change the immigration law. It’s only a remote theoretical possibility that the US could fix their immigration system.
No idea how reliable that site is, but it says Amazon.com sponsored 16,299, Amazon Web Services sponsored 5,056, and Amazon Development Center sponsored 2,119. So 23,474 in total.
Edit: I see a note that this is APPLICATIONS, not grants. Nevermind, that's probably not accurate.
Overall the claim that Amazon takes 25 percent of H1Bs is extremely incorrect.
But if I go into USCIS's H-1 data hub, I can find some information. For FY-2022 Amazon had 12.5k petitions approved. But drilling into the data we see that less than 4k of those were for _new_ petitions - the others were extensions of existing petitions. 4k out of the H-1B quota is less than 5% (there are 85k new H-1B visas per year). But even that is an overestimate because a new employee transferring to Amazon will require a new petition but won't count against the quota.
Overall, the best guess would be that Amazon use low single digits percent.