It's not the job of journalists to simply parrot corporate press releases. In fact, one could argue that, without added disclaimers, such promulgation is borderline unethical. If a corporation's views of their own products were always trustworthy, why would we even need benchmarks and independent analysts?
Awarding a best-product title to something unseen and unreleased is an obscene breach of the trust between journalists and their audience. Ryzen 5000 mobile is certainly hotly anticipated, and it very well may turn out to be the "best CPU of 2021". But it may also be eclipsed by some other CPU release, it might underwhelm, it may be delayed for unforeseen reasons, or it may even have some unlikely but possible technical flaw that turns the entire release into a fiasco.