Will a collection of 100 beers collectively be worth more 20 years from now than their value today? Different beer bottles and cans (with contents) from different places collected in the past 3 years.
No for the cans; maybe for the contents.

While it's hard to predict the future, we can infer from the past.  As it stands, beer cans as old as 40 years are pretty much worthless (with a few exceptions).  This is because right around the mid 70s, beer can collection as an activity exploded.  Beer cans before that point became valuable, but beer cans from after that point were heavily collected (up through the present day), and are therefore pretty low value.

TLDR: There exist too many well-preserved beer cans from the current era for them to be worth anything in the next 20 years at least (and probably well through the next 40-60 years).

That's just the cans, though.  Exceptions might be very specific beers known to be age-able for decades.  Unfortunately, most beers just don't age that long.  Even a hearty barely wine usually peaks, at most, after a couple years.  The Stone Vertical Epic 020202 series was meant to be aged 10 years, which is unusually long for a beer.

If you could find a beer you reasonably believed would improve over the course of several decades, you might be able to get some money out of it if it were stored properly.