Of course, if you study poker strategies intensively, you can improve significantly as a player. But there is also a certain danger, namely that of insecurity. If you change your playing style because you have just read a book by a professional poker player, this often leads to both regression and progress.
Current trends
Lately, we’ve seen more and more young players being extremely aggressive and having some success. Concepts like “three bet light” (raising frequently before and after the flop) and even “four bet light” are becoming more and more popular. Old basic rules like “juicing is right” are being questioned. In contrast, there are other strategies like the “ball”, represented by one of the most successful (and popular) poker players of the last 10 years, Daniel “Kid Poker” Negreanu.
Find your poker style

Ultimately, every poker player has to decide for themselves which elements they want to incorporate into their game. This is where their own personality comes to the fore. Anyone who generally avoids high risk will certainly not be successful as a hyper-aggressive player. Likewise, someone who enjoys playing will find it difficult to mark themselves (tight-aggressive).
Of course, this doesn’t mean you shouldn’t vary your style, quite the opposite! A universal truth is that you can’t be too predictable. This can be achieved by deviating from the main line in not so big hands. However, in existentially important hands, you should play what suits you best.
My experience
In my first major live tournament (LAPT Peru 2014), with extremely hard and cautious play, I managed to finish 22nd (out of over 1,000 entrants) in the Main Event ($1,500 buy-in) and win a side event ($300 buy-in) Turbo buy-in) on a day off. Shortly after, I played another LAPT event and qualified for the Highroller tournament with a $5,000 buy-in.
Unfortunately, I was eliminated because in a crucial hand, as chip leader against the second player, I went all-in with AA vs KK and my opponent flopped a king. This was just before the bubble, and if he had won the hand, he would have been able to continue playing with an overwhelming lead. In any case, you would have had a good chance of winning the top prize of around $200,000.
Anyway, I decided to learn more and improve my game. As a result, I started playing more hands and at the same time more aggressively. Unfortunately, I didn’t succeed: because of my riskier play, I was usually eliminated early, sometimes despite having a very good hand set.
It was only when I focused on my true strengths (rigidity, patience) that the results improved again. For me, this is confirmation that you will only be successful if your strategy fits your personality and uses your strengths. In my opinion, this is true, even if it makes your weaknesses a little more vulnerable in some ways.
Aren’t poker books worth reading?

This must be said in the negative! Even if they are books that promote a different style than yours, they are worth reading. After playing at a table for a while, you can often tell which opponent prefers which style, and studying these styles gives you the advantage of getting into your opponent’s head, making it easier to see through it and beat them.
It also doesn’t mean completely rejecting all the components of a strategy. Sometimes when you read a 400-page poker book, you’ll just find one variation to add to your game. This way, you’ll gradually become a more complete player without giving up your style!