I am sort of against this for the very reason they tried to sue Microsoft for "bundling" software for free that others were trying to sell.
1) It stifles competition and innovation.
If for example all the manufacturers "standardized" on one design, the others who cater to the industry would go out of business throwing folks out of work. We would be stuck with what ever design was accepted and innovation would be eliminated because with no market, why bother.
2) Replacing the "standard" Line monitor with an after market one would be beyond the average DIY'er because even trying to find it would be a challenge. Most folks would not even attempt it even if there was an improved model to go to.
3) It might force us to accept crap. They could advertise they had "built in" line protection while using the cheapest and least effective solution to keep their costs low and the profits high. You would have a false sense of security. There is a big difference between a surge protector that has a 500 Joule rating and one with a 3600 Joule rating. You can buy a surge suppressor for $9.00 or one for $500.00. Which one do you think will wind up in your camper as "standard"?
Surge protector - Wikipedia, the free encyclopedia
4) Who would build a better mouse trap? What could they possibly sell it for that would entice the mostly uneducated public away from the "standard" one?