>>23372918
Copyright issues. Revising old copyrights is way more trouble than it's worth especially when you have dozens or hundreds of them. Much easier to keep them the way they are. Also, the use of the term "Kamen" serves as good point of separation between Heisei Phase 2 and the rest of the series.

Also, the Wang brothers developing Dragon Knight at the time, pushed for the series to be called "Kamen Rider" because that's what they knew it as growing up.

And according to this video, Dragon Knight's use of the phrase "Kamen Rider" to transform; inspired Decade's staff to use the phrase "KamenRide" for the Decadriver. Which would also explain why it's "KamenRide" and not "MaskedRide".

https://youtu.be/_HpzTtCJY0o?si=921zspvZyS3tCZ8A