The article and social media response highlights a few problems. Chiefly, that high speed E-bikes are effectively moped-class vehicles that people are riding as if they are bicycles.
And by that, I mean they can be ridden very dangerously. Such as on a pavement or other pedestrian zones where people do not reasonably expect a fast and quiet vehicle to be present.
I've been learning how to ride a bicycle lately as an adult, and I have rapidly gotten the impression that education around bicycle laws is lacking. Because it is actually illegal to ride a bicycle on pavement that is not marked for such use. People either don't know, are uncertain, or willingly use a pavement anyway for conveniance because nobody prosecutes for it. So many cyclists use pavement that for all my life I thought it was normal and allowed.
Cyclists who take that behaviour into an E-bike and use it the same way, especially at high speed (modified or not), present a significant risk to everyone involved. I find the following statement perfectly reasonable:
Sergeant Gareth Davies said: "While it's not illegal to own an e-bike with an electrical assistance or power output exceeding 25 kph and 250W respectively, you can't ride it on the public highway as a regular bike without registering and insuring it like a moped.
The assertion that most of them siezed in the article appear to be from food delivery drivers is interesting because it speaks to a greater issue in that industry. That the results we're seeing here could be driven by unreasonable work expectations and poor pay, encouraging these workers to use E-bikes as a cheap and hassle-free way to do their work. You can see that in how some respond to this issue with comments like:
One person commented: "Targeting hardworking people just trying to get by, well done."
Another added: "This is so hard to look at. These people are trying to earn a living and get £3 per delivery and you do this? This is vile and disgusting!"
I can agree with that sentiment, E-biking should not be targeted unreasonably. They are a good tool for when a regular bicycle does not fit your needs for whatever reason. Just so long as, like all vehicles, they are ridden safely and responsibly.