The whole PVC thing is way overblown
Vector cutting sign vinyl is mickey mouse compared to rastering large areas of it or cutting thick PVC. PVC release chlorine and/or Hydrogen chloride gas which is nasty and combines with the moisture in air to make HCL acid (hydrochloric acid is the stuff used in pools to balance the PH) It is a lung and skin irritant. It produces Dioxins as well , also nasty.
If you do enough of it continuously , it will eventually generate enough hcl and attack the metal parts of the laser and corrode them. The amount of Hydrogen chloride produced cutting a bit of PVC sign vinyl now and then is hardly worth mentioning and the chlorine is far less than a std chlorinated pool releases hourly. If your pex or other stuff you cut has a plastic covering and you cut thru that , you are most likely cutting PVC anyway. 3m make a range of polyester laser friendly vinyls. We raster and laser cut them extensively for sandblasting and acid etching resists. The colours are limited and prices are high compared to bog standard sign vinyl however.
I know someone that uses a laser with a scrubber unit to detoxify the exhaust that cuts vinyl on a continuous basis , his platforms last a yr to a yr and a 1/2 and then they dump em and scavenge all the useable parts like the tube , PS , motherboard etc and just order a new motion system. Its an application that cant be done with a vinyl cutter which is actually a better and far cheaper way to cut pvc sign vinyl than a laser which leaves a lousy edge on the vinyl and often remelts the stuff together or doesnt kiss cut well. The real reason to use a laser is for rastering fine detail a vinyl cutter could not hope to cut or any mortal user hope to weed if it could be cut. There are plenty of other materials even more hazardous and nasty to cut , like nylon (produces hydrocyanic acid gas , same as death chamber stuff) or teflon (produces phosgene , nerve gas)