We see the government wants to trace IP addresses to a person.
We know that is impossible, but tracing IP addresses to a subscriber is more possible. For a lot of ISPs though this means using some data from CGNAT gateways, which is a lot of data to log. It may be that some is logged for a short amount of time, for the ISPs own usage (diagnostics, abuse, etc), but it seems the government want to log everything for a year.
Even so, it is generally a tad pointless for the purpose of identifying a person responsible for something for lots of reasons.
However, we may well see side effects of this if the happens. Obviously the legislation has rules around this, and RIPA is relevant for access to the data, and so on, but once you have the mechanisms in place and the tools and investment necessary, data does not stay compartmentalised.
One of the ways it can cause problems is with the courts.
We have already seen a number of court orders on large ISPs to block access to web sites. This is something that never used to happen even though the law allowed for it. The reason it is happening is that there is almost no cost for an ISP blocking child abuse images to extend that to block some extra web sites. So we have a side effect of something that people think is sensible, such as blocking people encountering child abuse images by accident - in that the technology to do that is now extended to other things. It was a side effect some of us predicted but I am not sure we expected the issue to be with the courts.
So will we see the same side effect for tracing IP addresses. We may see many more Norwich Pharmacal Orders to ISP. If there ends up being an API for tracing IPs to subscribers for ISPs to work with RIPA, then how long before the courts demand that the API is provided to copyright trolls as well, as no extra cost.
Obviously breaching copyright is not right, but neither is the way that many of these company intimidate and embarrass innocent parties that are just the bill payer for a household in to coughing up money when they have not done anything wrong.