I understand where your coming from and if you have the time, tools and skill no doubt you can build a trailer for 12k.
But if your a new company building an off road trailer in the US and pay your employees a livable wage and make a profit to stay in business then 45k seems reasonable to me in this market.
This pretty much, breaks down to an opinion of value. According to statistical income/asset ranges, I'm in the top or upper 10%, retired and comfortable, not wealthy but far from broke.
When I have purchased any "major" item, I have never made my purchasing decision based on how well a manufacturer paid their labor force, while I have passed up bad actors, prison labor and other dirt bag operators, I don't expect to pay a premium for a company to simply do the right thing.
That trailer is over priced, I say that based on my research on travel trailers for the past year, I'm no expert but not a chump either.
What I see is eye wash, marketing on the "off road-overlanding" concept and expecting about $15,000.00 for the dream.
You can look up the materials to build those cabinets on Amazon, not cheap, but as a builder those units shouldn't be more than $2,000.00.
Notice the suspension, not so much about quality parts from specialized fabricators as the components being made "in-house" with lighter gauge steel, and I doubt the shocks are Bilstein's reservoir types.
As to this market, I'm finding travel trailers at reasonable prices, especially in the used market for late models. You can get a trailer with great bones, well laid out floor plans for under $15,000. Keeping the major appliances you can replace or reinforce cabinets, bedding and bath, you can have it done and going all-in, be under $25,000 for basically a new remodel built for your purpose.
I'm not interested in a new title that means very little in short order or if factory employees can buy new cars every year, or even every 3 years.