I have seen some discussions around this topic with some various solutions. Spanning from preventing someone winning more than once, to creating specific pools where you can’t have too many tickets.
I’m personally of the opinion that it’s unfair to prevent someone from winning multiple times. I appreciate that the pools are worth what they are due to the high numbers of tickets bought by a small handful of addresses. Without them the prizes wouldn’t be as impressive.
Similarly creating a separate pool with ticket caps might just achieve two things:

The larger investors don’t take an interest

They simply spread their tickets across multiple addresses.
I was thinking about this issue and came up with a slightly different approach. I haven’t seen this in the forum yet, so I apologise if it has already been raised previously.
My idea was to have subsequent wins decrease slightly in value, by some X percent, which scales with the subsequent number of wins. With the value of these decreases being distributed among all ticket holders, proportional to their position.
For example,
The current setup is
Total winnings per winner = (prize / numberOfWinners) + (loot box [if first])
For the purpose of this example I’ll ignore the loot box, but the first winner will still always receive it.
Proposed setup
This will only occur if the same address wins at least twice.
Say there are 3 winners in the pool and each winner receives 33%, the new setup would look like:
Win #1
Address receives 33%, as normal
Win #2
The second subsequent win is decreased slightly in value and the difference is distributed proportionally.
Say the decrease factor, X, = 5%
Address receives 33% minus (5% of 33%), which is 33%  1.65% which is 31.35% of the prize and 1.65% of the prize is distributed proportionally.
Say then that they win all 3
Win #3
Address receives 33% minus (2 times 5% of 33%), which is 33%  3.3% which is 29.7% of the prize and 3.3% of the prize is distributed proportionally.
Hypothetically if there was a 4th win in a row then it would be 3 times the X factor, and so on.
Using a real example if the prize was $100,000 and the X rate was 5%
Win #1 = $33,000 with no distribution
Win #2 = $33,000 minus 5% of $33,000 = $31,350 and $1,650 is distributed.
Win #3 = $33,000 minus 2*5% of $33,000 = $29,700 and $3,300 is distributed.
In this example the duplicate winner will receive $94,050 of the $100,000 prize and the other $5,950 is distributed proportionally.
Things to consider

What should the factor of X be? 1%, 5%, 10%?

Should X increase for each consecutive win?

Should the duplicate winner also receive part of the distribution? I personally think they should, as again, they are largely contributing to the prize.
I love the concept of Pool Together and I feel this change might attract more players. Looking at the odds of the high holders can be a little daunting sometimes. This at least gives people the chance to earn even a small amount in the event that a large holder wins multiple times.
For those who stuck around long enough to read all this I appreciate it and welcome any feedback.