10% tongue matters for cars where limit is close to what you're towing. Barely matters on a full size truck or likely even quarter ton.
Take everybody's advice with nuance in mind depending on what vehicle they are towing with, what total weight is and whether they are being smart about it.
A Honda Civic can tow 5000 lbs at 3mph safely while even a 1 ton truck can't safely tow full 5000lbs at 100mph even though it's rated for much more.
Speed is a HUGE factor in equation of safety and comfort of towing and risks increase exponentially.
Even with that said besides speed tongue weight can be absolutely crucial at speed.
Even with tongue weight it's a good idea to have a weight distribution hitch to help with away control for any enclosed.
All I'm trying to say towing is a great means to an end of track days and other uses but unless you have a real truck (which I didn't want to own a truck) there are a lot of caveats and considerations to make it safe.
Full size trucks are so good at what they do and are so overbuild most people towing don't have to worry about anything and they barely even feel a trailer below 5000lbs.
I only tow like 6 times a year total so I'm fine with compromises and overthinking it for those 6 days as long as I don't have to own a truck for the other 350+ days
You should be fine with any vehicle that's rated for 5000lbs. If you're cutting it close, consider aluminum trailer.
My 18ftx7.5 enclosed with car and tools and spares is around 4100 lbs.