There are an estimated 7 million research scientists in the world. Last year, Xi, Wang, and Kong (2021) published a review of survey studies on scientific misconduct. About 3% of participants (all scientists) anonymously admitted to scientific fraud (e.g., fabricating data, plagiarism). Assuming that the 3% estimate holds for the population, that means 210,000 researchers (7M x .03) have engaged in very serious misconduct at least once.
Also, 12.5% admitted to questionable research practices (e.g., harking, p-hacking). That's 875,000 scientists.
In your judgment, given these numbers, how big of a problem is scientific misconduct?