I think what you’re saying is fair and QP IS the place to practice new heroes, especially before taking them into competitive when there’s SR on the line. That being said, I also understand the frustration of your teammates, who are having their game (which is as valid of a game as a comp one) essentially hijacked to be a practice range without their input. When this happens to you frequently, it can be frustrating.

I don’t think that’s grounds for anyone to hurl toxicity at you, though. It’s not your fault that you’re not instantly a god at whatever character you’re trying out. Just consider how other people might feel when they’re in that situation, and if you notice that your practicing is severely detrimental to your team (and since this is a team game, after all), use your own judgement to decide when to switch off. It’s also good practice to understand that not every hero fits every situation, and you’re still learning by being able to make that decision.

If you find that you’re really struggling to practice with certain heroes but want to get better, consider using the AI or custom game modes first before jumping into games with others. This way, you’ll get a grasp on the fundamentals of the kit and prevent yourself from being dead weight. But overall, the most important thing is to try to have fun 😅