Right now they're not accessible to everyone, they're accessible to rich people and a lottery of poor people.
When prices of a good or service goes up, it incentivises other manufacturers or service providers to produce more of that good or service, which increases supply and puts downward pressure on prices.
So to answer your question, higher priced tickets increases supply, which causes lower priced tickets, which benefits poor people.
Eventually prices reach a level where supply and demand match and (for example) concerts are as cheap as they can be given their cost and the demand in the market for them (including the demand from poor people).
This EconTalk episode on price gouging during a natural disaster was very interesting, and somewhat related to this topic: https://www.econtalk.org/munger-on-price-gouging/
Guess why people still go to Sziget or Woodstock.
Also guess why it's impossible to just click your fingers and pull an unlimited number of Woodstocks out of thin air.
The fact that there is a limited number of Woodstocks is irrelevant.
There are other organizers and bands who can also offer concerts, and at a reduced price compared to the premium that something like Woodstock would demand. That's competition, and it puts downward pressure on concert prices in general, thereby helping people on a tight budget.
Why do you think that is?
Hundreds of shitty ape pictures that anyone has access to view has not changed the price of entry to the Louvre.
You do not reduce the price for one form of art by having other artists available. They are all different, and people will want to see one and not another.
No offense, but you do not understand art.
Yes, there are a lot of bands that could sell higher priced tickets but don't because they want to be accessable to everyone, not just people with money to burn.