For someone starting out, it is easy to think that the advertized capacities of a model apply to all configurations. Many new people to towing also fail to understand the amount of tongue weight needed to tow a typical trailer. Add the salesperson into this mix that has incentive to sell you something yet may lack the knowledge to sell you the appropriate something and you have created a lot of misconceptions.
Interacting on a forum with others that just countered everything you thought you learned above can be a shock - You just spent a large amount money on a combination that people are telling you is unsafe and that you should not put your family and others in danger by driving it.
I have hauled and towed well above the ratings on my previous trucks without issue. Although I do not encourage others to do the same, I did learn things along the way on how to mitigate handling issues either through additional/upgraded devices or driver operation. If someone has handling issues, I will share what helped me in the past.
I don't feel that exceptional driving skill will fully compensate for poorly mated equipment, but I also know you cannot give the untrained a professional tool and expect professional results.