After sr.wikiquote.org logo was successfully updated in T168444, en.wikiquote.org logo should also get updated i.e. refreshed so that it reflects last version of logo uploaded to Commons (many corrections have been made meanwhile).
If this is done successfully, then https://upload.wikimedia.org/wikipedia/commons/thumb/d/d6/Wikiquote-logo-en.svg/150px-Wikiquote-logo-en.svg.png and https://sr.wikiquote.org/static/images/project-logos/enwikiquote.png should be same; now they are not.