PLF, GMP who knows. The last I heard was that Europe as a whole in 2024 did only slightly more tourism than pre-COVID. Sort of what the PLF thing shows ... maybe. But what the study summary doesnt describe are the hot spots. Spain and Portugal for instance. Then some areas are still not recovered, like parts of Eastern Europe and a lot of Europe is pretty much sitting where it was in 2019. Then there are the one-off things like the Jubilee in Italy. The the PLF is a factor of the amount of serivce to a location moreso than the popularity of a location and there is no way you or I can examine that, so all in all the article really isnt much of a tell for a tourist.
You want cheaper prices be flexible and stay away from the current hot spots. Montenegro instead of Croatia for instance. Airfare is only a part of the cost, you can offset it maybe with cheaper accommodation or by visiting an under discovered region; maybe go to Slovakia or Montenegro or Romania or Bosnia or Bulgaria this year as opposed to paying the prices in Germany or Austria for instance. Of course, whats a holiday if its not to the sort of place you want to see and will enjoy. Decisions, decisions, decisions.......
Abandon all forumulas as to when to buy plane tickets and just track the prices for a while and pounce when the number is reasonable for you.
Otherwise relax and have fun on holiday.