Actually, I think this move has got nothing do with the UK specifically. It's to do with the EU VAT changes that make Luxembourg no longer advantageous to sell from. Those changes came at grievous cost to small businesses but the EU doesn't seem to care.
Anyway. This whole thing is bad news. The UK is currently trying to throw the idea of tax law in the bin by passing stuff like the "General Anti Avoidance Rule", which literally says anything the government doesn't like is illegal (retroactively), i.e. it's not a law at all, but rather a return to the time of kings. The "diverted profits tax" amounts to the same thing - if the government sees something it wants, it'll take it, and there's nothing resembling normal legal processes to stop them e.g. no requirement to specify exactly what they will take and when.
In effect the UK is enacting an equivalent of America's civil asset forfeiture schemes, but for business rather than individuals, and with the justification of balancing budgets rather than the war on drugs. But they amount to the same thing - the law says they can seize money whenever they like, without needing any meaningful justification. And if you don't like it you can appeal to the same people who took the money in the first place.
It took decades of civil asset forfeiture abuse before it became bad enough to trigger real investigations/reforms in America, and the damage inflicted on civil society has been huge. When the laws were passed in the 1980's it's safe to say that the authors didn't really think through what would happen over the long term, even though the outcome was rather predictable.
I think what the Tories are doing will be the same - if these new taxes aren't struck down by the courts then in the long run they will inflict lasting and serious damage. It'll be hard to see at first because the new powers will only be used against very high profile and controversial cases, and then as governments constantly find they're out of cash, they'll go on tax raids ever more frequently with ever more dubious justifications as to why it's OK. And the impact will be that some businesses leave, others simply don't establish bases in the UK at all, and some businesses that would have been good are just never created in the first place.