The manufacturers build the type of trailers that sell. The majority of the owners know that they are made as quick as possible but really do not care to spend more.
If you want a better build look to Airstream, Lance, Arctic Fox, or the shell type like Casita, Scamp, Bigfoot.
If you really want 2x4 and 4x4 home style construction the is always tiny homes type trailers.
Oh yes, bring money and a big truck.
There is little incentive for the market to change, there are already enough manufacturers to match the quality you are willing to pay for.
