The rubber trees burned some years ago.
Ever since, most things are made with a blend, or without natural rubber. This is why seals leak brand new, dry up, hoses dry up in like 3 years and break, tires have a 5 year expiration date.
Humans were very clever with chemistry and made many variations of what is basically a thermoplastic rubber. Initially this was added in small amounts to rubber tires for longer wear.... remember in the late 90's when we got introduced to 75,000 warranty tires that actually were quiet and rode nice? Well, when the rubber part of the equation got scarce and pricey, they put less in.
PLUS,
Americans love Walmart. So they go there and buy tires of all things, made in China or otherwise. Ain't no rubber in chinese goodyears. Then they use soft compound to make them quiet, and they wear out in 20k miles. But people go buy more, cause they are cheap. that is the story of most everything from 1998ish to 2018ish. Now people are fed up with it because everything is like that. but the good stuff went bankrupt so we get what we get now.
If you want good smelling, rubber, not chinese tires, they cost a lot. Most brands have some lines they make in this country yet. goodyear/Kelly still makes a few things in Illinois for example. Depending on what you are after Coker might have something for gonzo money. otherwise you get tires made of the same stuff as dollar store hammer handle grips.