I’m not sure you know how this works.
Flippers are not responsible for making items that used to be 250 mill and are now 5B.
What flippers do is find items that are being sold for under the marketvalue and put them back up for trade at their current marketvalue.
Whats causing items to gain value/increase in price is simply the longer a season goes on the more expensive the top % of items will be and lower % of items will get cheaper.
The demand for the top items will increase and thus the value and the price goes up, it has nothing todo with flippers. Likewise the demand for mid tier and lower tier items goes down as people dont need them anymore and thus the price goes down.
It’s no different to real life, having money under your bed is the worst possible thing you can do, it will loose purchasing power over time as things get more expensive. Same thing here.