>some of main reasons of its decline.

Also Youtube, and justifiably so for once.

NicoNico was simply obnoxious to use even in its heyday, while you could just open a Youtube vidja and watch. Once Youtube incorporated livestreaming and chat, it was over for NicoNico.

You're comparing a completely domestic webservice to a prime Google product. I do agree sentimentally but logically that's insane. I mean, ever given a thought to Twitch!?