Yes, there is evidence showing perfectionism to be associated with various negative outcomes. We've covered some of Flaxman's research before, in which people with perfectionist traits were found to recover from stress during vacations, but see that benefit dissipate quickly once they return to work. In general, perfectionism is also associated with weak productivity thanks to putting off completion of tasks or hitting walls in creative areas, and to personal frustrations.
However, evidence suggests that there are actually two kinds of perfectionism. At the heart of the problematic kind is a concern for how others see you, leading to doubts in your own worth. This so-called 'evaluative concern perfectionism' leads individuals to avoidance as a method of coping with stress (see link for problems this can cause) and review of the data suggests these people experience higher levels of hassle in life, along with more distress. But crucially, there is another strand of perfectionism, one that is primarily self-focused and concerned with personal standards. This strand is associated with active coping strategies, and with reaching higher levels of achievement. However, for these people, the higher amounts of life hassles - and possibly distress, although the data is less clear - remain. Flaxman emphasised that while the two strands involve different internal states, the behaviours can look identical from the outside.
One useful way to look at perfectionism is as an underlying vulnerability factor. Day-to-day perfectionism can chug away in the background, influencing but not determining behaviour, and if it's self-focused, it may facilitate better performance. But when experiencing achievement-related stress, such individuals encounter high distress. At its extreme, in the clinical context, failure is 'a fatal blow to the self', and can be associated with self-harming actions.
Flaxman urged his audience to foster more workplace-focused research in this area, as the field is still overwhelmingly clinical or student-focused - despite the fact that many of the survey instruments used explicitly reference work-related stressors, which often have to be removed before data is collected! And he showed evidence that interventions can be successful: his work with Acceptance and Commitment Therapy, a mindfulness-based approach, can help improve psychological flexibility, increase resilience, and reduce perfectionist attitudes.