We're stuck with 25 km/h here in Australia
It is the European, not the British law. In theory, Australia should get a better access to Euro e-bikes (that are made in Taiwan anyway) but it is not so (you certainly know what I mean).
We at least have the option to buy an S-Pedelec (45 km/h) in Europe, register it, insure, and ride legally. S-Pedelecs are rare (e.g. Vado 6.0, Allant+ S, R&M HS...) and the most expensive in the segment. The police told me they only found
two registered S-Pedelecs for Poland, one of them being mine. You Australians even don't get such a chance, I guess. The New Zealand e-bike law model should be embraced by Australia! (Only a limit on the nominal motor power).
but from what I've seen around the derestricted ebikes are pretty niche.
I don't think the law-abiding German people derestrict their e-bikes. France has defined draconian penalties for riding illegal e-bikes. Meanwhile, any Pole tries to derestrict their e-bike. Take my Vado SL as an example. The bike is made the way a weak cyclist typically rides it within 25 km/h even derestricted. Adding more assistance and pedalling harder, the e-bike actually would not ride faster than 34 km/h on the flat and with no wind. I
had to derestrict my SL because I would be eliminated from group rides with traditional cyclists otherwise!
And the future looks really bad. Big market players must have got a clear signal from European authorities to put an end to e-bike derestriction. Any time I fancy buying yet another Specialized e-bike, I get sober with this thought: "Why should I buy a 25 km/h road e-bike I wouldn't be able to derestrict?"