You're right that there's a problem with recollection. I can't remember going through such a phase either, but I know I did because there are photos of me as a baby sticking things in my mouth (although in the photos these are things designed for babies, like plastic cubes big enough to not be swallowed, but small enough to be easily handled by a kid, etc). In fact, I had no idea of the ages involved, so I searched online and found that most babies start this phase around 6 months and usually stop by 12 months, although some kids continue on until 3 or 4 years old.
But yeah, materials like the rubber in my inner tube... I'm pretty sure my parents wouldn't have allowed such stuff near me as a baby, likewise I wouldn't have been allowed near boxes of matches etc. I also can't imagine I'd ever have decided as an older child that I should try licking a bike tube or the striking surface of a matchbox. And so, I'm about as confident as I can be that I'd never have licked an inner tube in my life, but I can make a good guess from feeling it with my fingers what it'd likely feel like on my tongue.
There's very little where I'd go as far as to say "I cannot imagine what it'd be like", except maybe for things that would involve a chemical reaction, and where I might have some idea from extrapolation with foods - e.g. fizzing, an exothermic reaction, etc., but wouldn't necessarily be able to guess from looking or feeling with my fingers what the result might be. Most of the interesting ones are turned into food anyway, e.g. sherbert dip or sour sweets.
I definitely have had some surprises in later life - I remember first having ox-tongue when I was in my 20s and finding the texture quite uncomfortable, and since high single-digit ages, I've never been able to correlate the texture of liver with something that's edible.
I guess another example is with unfamiliar "exotic" fruits - there are some that would surprise everyone with their taste, but you can guess most of the texture characteristics of a fruit just by looking at it and cutting it into pieces, and you might be able to have a guess at taste from its smell.