Basically she's saying chat apps in the UK shouldn't be allowed end-to-end encryption.
So the terrorists will setup a chat system that look like payments.
In the mean-time, the UK government will use our chat to identify harmless political dissidents, groom them online and then fail to incite them to violence. Given previous performance, they will meet some of their targets, get a few pregnant and then get sued 20 years later when someone reports on how idiotic the police and spies really can be while everyone sane scratches their heads about the targeted pro-solar-power "terrorists", who happened to piss off Lord McOil who had a quiet chat with his Eton buddy in GCHQ which got them classified as dangerous.
After 5 years, Boris, our new PM, will decide to give government departments access to find benefit cheats and illegal immigrants. The system they'll build will cost more than they recoup and will be a drop in the bucket compared to what they could have recovered if they had spent 1/10th of that money chasing rich tax dodgers.
A couple of years later, they will give councils access to the whole country's chat to try and catch some fly-tippers.
In this time, the civil servants will actually use the system to stalk ex-girlfriends, random crushes and celebrities or spy on wives and husbands.
Eventually, some civil servant will accidentally leave a hyper-storage-cube on the bus containing the last 5 years of everyone's chat and it'll turn up on 4chan.
The resulting misery and damage will be justified by the government because they once caught a "terrorist" who was standing in the street screaming "Allah is great" and stabbed a policeman. In reality he was a normal guy who had suffered from Bipolar Disorder but the NHS couldn't afford to treat him and classified him low risk, so ended up having a breakdown.