You might need to look at the individual manufacturers to see if they have placed artificial demands on their employees which caused a reduction in their workforce which caused their production to halt. Requiring your employee to be a gunnies pig and take experimental injections in order to come to work would be one cause of a slow workforce. The reasons can be obvious. Blaming slow imports might be a reason too, but if the lots are full of cheaply-made RVs then someone is getting parts to build them.
SInce there are RV lots full of RVs I would assume there is no shortage of RVs in general, only perhaps a shortage of a particular manufacturers models due to self-inflicted harm to their bottom line.
It is hard to take this question seriously when RV lots are full. Either people are not buying, or the problem does not exist.
Mask are useless and the vax makes you more vulnerable to any illness, esp the current one that is about gone by now.. Yes, tell your employees they take deadly drugs and wear health-harming petri towels on their faces all day in order to work and you get a weak work-force, more sick days, retiring early employees, no-shows, hospitalized workers who die from remdesivire or ventilators etc, then that company will of course have issues.
We are in this mess because we allowed it to happen, we did it, the politicians only suggested it to us.