There are quite many such websites - Cointelegraph, Coindesk already mentioned by other members, Bitcoinmagazine.com, CCN.com and others. I can't say which one is the best. But still, we can't 100% trust in these websites - sometimes they are biased or posting sponsored content (promotional articles) without disclosing it.
Why did you called Coindesk as decentralized platform? It's centralized platform, same like all other similar crypto news websites.
the best blockchain news platform is from telegram,twitter and from facebook.
Very abstract answer. Telegram, Facebook and Twitter are just social media platforms, while OP asking about specific new websites.