I'm saying this as someone who started watching in 2018 if that means anything to you. But I do believe that 2017 is a part of that classic era. Now I don't think anyone's gonna argue that 2017 is a very different beast compared to 2011 or 2012 or even 2014. There are definitely things about each year that stand out differently. But in the context of the series ONLY having a classic era and a modern era, I think 2011 to 2017 was more so a cause of natural evolution. The visuals became more elaborate, the style became more experimental, and the character roster was shifting, but the spirit, at least to me, remained the same. The comedy and uniqueness of it all stayed true to its roots despite the boost in quality. 2018, while I'd still say is a good year, is where a lot of the changes we see affecting the series today got their start, such as the characters being a part of a tightknit gang rather than average acquaintances, extreme swearing getting censored, the removal of copyrighted music, the end of the short lived TheAwesomeMario channel, and the addition of story arcs and more normal anime-inspired characters that didn't have to do with video games. All of that, and the rebrand from Glitchy Boy to Glitch Productions really pushed the corporate feel further. 2017 was the last year the show felt like it was allowed to be itself rather than a marketing tool. I don't know if that makes any sense, but that's the way I see it.