Different beer bottles and cans (with contents) from different places collected in the past 3 years.
Not likely, unless there are some rare beers in there that benefit from aging and are kept in the right conditions.
Most beers will oxidize over time, even with a sealed cork or cap a minute amount of oxygen can permeate the seal, over the course of 20 years this could damage the beer. Some companies may wax dip their beers as well, in many cases wax dipping is more for aesthetics but can also help minimize oxygen exchange for periods of long storage.
Only certains beers are suited for aging, such as some lambics, saisons, Belgian quads, and high ABV stouts and barleywines, to name a few. Even for some of these it may be noted to cellar for no more than 3-5 years.
For long term aging you also need to maintain temperatures in the range of 55°F. This temperature should be held consistently with any major swings up or down being avoided.
Outside of this you would need to have beers that are rare and highly sought after today to have even a chance of them being valuable in the future. Even if you picked out 20 of the most sought after beers today it's important to remember tastes change and they may not be sought after in 20 years. Just look at the changes the American craft beer environment has gone through in 20 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.