And since we're here, no, the indiscriminate monitoring of emails and phone calls has not been going on in the UK for some time.
in the UK, traffic data but not content of phone calls is physically held by the telecoms companies. Email traffic data plus often content is held by the ISPs. Police and security forces have to apply for individual warrants to get any data.
The warrant system limits the scope of data to what is proportionate for each instance, balanced against privacy.
It is simply not possible to conduct the sort of indiscriminate fishing that appears to have been happening in the US, because the security forces never have their paws on whole telco/ISP databases.
Tracking web usage is a different area that I'm not up to speed on, but IIUC retaining web use data is what the so-called Snoopers Charter would have allowed - and Parliament have recently rejected this bill. Even then, IIUC, this would still have seen data retained by the ISPs, and the state requiring warrants to make queries on it.
(Willing to be corrected on the web usage bit if anyone knows better.)