As I do my best to eschew the discrimination towards Matt Ward's Spiritual Liege-fetish and GW's ever growing fascination with mangling established lore for profit... I do see the value for new and returning players to make something that can arguably fit into the lore AND make sense on the table top. These are NOT the 10th generation of remnants of the legions that split into chapters 10 millennia ago. These men have been created by the returned Primarch, genetic prodigy of the Emperor himself, to fulfill an impossible purpose. Where the descendants who have fought and died for over 10,000 years to ensure the Imperium survives, the Primaris brethren will lead the charge to attack our enemies.
Now, I know and feel the frustration many feel towards GW for basically shoe-horning in all this hopelight into our grimdark, this new lore into our established lore, and these obviously truescale-esque minis in to replace the current range in time. That said, we all know what kind of company we're buying from. It's a business and they want to make as much profit as possible. In turn, we do get miniatures that have perhaps the industry's top standard in detail and material quality. And while the rules ARE balanced to make profit by showcasing the power of their new products, like the Primaris Marines, they do sometimes dial things back in their FAQ and e-codex data. Besides, if there's something that you don't like, I always say fix it or impose limits.
On a personal note, I'm actually getting into the idea of a very small, very new, very elite chapter that's making it's debut in a trial by fire against the worst the Dark Imperium faces. The Scythes of the Emperor are NO DOUBT going to make a return which is thumbs up for me and I'm really looking forward to making my own Primaris Chapter because, well, we CAN! Plus there's pretty cool scenarios, I think, for old chapters to turn traitor in defiance of this insult to their honor and deeds or be renewed and seek out even greater honor and new glories. For new chapters to rise, and old traitors to finally meet their deserved end! I have no doubt that the Sinister Seven will stick around but perhaps evolve into new enemies. I for one REALLY want to see a revival in Fabius Bile and to see a sub-faction in Chaos that has their own version of Primaris-level traitor marines. Perhaps Cawl and Guilliman aren't the only ones who've perfected a new kind of super warrior...
I have in mind my own Primaris Chapter and I can't wait to get them built, painted and on the table crushing Xenos and Heretic alike!