This is not just safety requirements, but also drug/alcohol testing, log book requirements, and US insurance. Keep in mind that in 2001 Congress appropriated the money for this.
And it is not just the above. The pilot program provided for additional monitoring.
Additionally, you could hardly say that the US trucking industry is a paragon of virtue. While there may be an upper tier of trucking companies who are compliant with all the regs, there is an much, much larger, lower tier who stay in business only by breaking regs. There are over 60,000 trucking companies in Texas. You should be pushing to inspect all US trucks to the same standard being imposed on Mexican trucks.
Very apparent you have never driven an eighteen wheeler through a California inspection station. LOL