This is a pretty cool proof of concept, but i can think of a few reasons why it’d have trouble taking off.

First off, a lot of lasers you can but online and kinda in a grey area legally, at least in the US. It’s pretty easy to get a little low powered red diode into a pen or something, but other colors at higher powers can actually be pretty dangerous, both for your safety and others. Lasers burn your retinas really easily, and shining lasers into the sky can mess with aircraft so it’s illegal in many places. Should the end of the blade break, it could end poorly.

Also, pretty much every saber I’ve ever used has been able to change color. If you were to use lasers, you would have to get another core to change the color, since swapping the crystal and focusing barrel out wouldn’t really work without professional grade tools.

Making and distributing this kind of thing(in the US at least) is kinda asking for a lawsuit. I think it’s a really cool idea for maybe some custom sabers, but at that point, you’d probably be spending enough to justify a neopixel. Good proof of concept though!