Think on it:

(i) Coming off a “hot streak” on the Sega Dreamcast with two of the most beloved 3D entries in the series (SA1/2), Sonic Team would go on to pump out a collection of highly underwhelming Sonic releases (namely, Sonic Heroes & Shadow the Hedgehog). Analogously, while not necessarily on a “hot streak” during the 3DS generation, Pokémon Co. would go from relatively fine quality to very underwhelming (LGPE, SwSh, BDSP).

(ii) Then comes 2006: Sega wants to bring big change to their once renown Sonic franchise, which had been dwindling in popularity. So, in honor of Sonic’s 15th anniversary, Sega rushes Sonic Team to churn out their most ambitious Sonic game yet: Sonic the Hedgehog (2006). With a strict deadline of Holiday 2006, however, developers only had just over a year to get the game ready and shipped. Predictably, this led to a nightmarishly poor quality release that left the Sonic brand fatally tarnished. Analogously, Game Freak — looking to bring about a similarly ambitious Pokémon game via introducing an open world gameplay loop — would force Pokémon Co. to pump out Pokémon Sc/Vi in time for the 2022 holiday season. While not as atrocious as Sonic ‘06 (and nowhere nearly as troubled in its development), the game did not come out very polished. The results was the lowest received Pokémon game of all time by critics and consumers alike, and has seemingly left the Pokémon brand in a fatally tarnished state.

(iii) Following the disaster that was Sonic ‘06, Sega — in an attempt to save face — would allow Sonic Team to take their time with upcoming mainline releases. And the results were impressive: Sonic Unleashed, Sonic Colors, and Sonic Generations. And while Sonic Unleashed would be panned almost as harshly as Sonic ‘06 — despite being considered as among the greatest and most revolutionary entries in the franchise by fans — Colors and Generations would be praised. Analogously, as pf present date, we only have Pokémon Legends Z-A, a game which GameFreak took their time with, and a collection of very promising next gen Pokémon releases down the pipeline. And while Legends Z-A has been panned by consumers — despite being considered among the greatest and most revolutionary entries in the franchise by fans — …well, the future has yet to arrive.

What do you think? Is Pokémon Legends Z-A the new Sonic and the Secret Rings? Or is it Sonic Unleashed? From all that I have seen, it had been nothing but overwhelming praised mixed with overwhelming rage: it takes many steps in the right direction (e.g. evolving the gameplay loop of Arceus, performing very well on NS1/NS2 without much compromise, solid story) but also still has much room for improvement (e.g. repetitive gameplay loop, slightly bland/small world to roam around, lack of VA).

I mean, Scarlet/Violet sold over 27 million copies, and subsequent games have continued to sell well, I don't think it really damaged the brand as much as some would like to think.

Yes and Sonic ‘06 (IIRC) sits as among of the best selling 3D Sonic releases. Additionally, Sonic ‘06 didn’t damage sales for future entries. Almost all games post-‘06 sold about as well as any Sonic game between Heroes and pre-‘06. The main damage was in brand reputation.

Given the target audience for Pokémon, critical reception and the core/enthusiast perspective don't really matter that much in terms of its ongoing success. One could argue that's true for Sonic as well, where its following will keep buying it no matter how crap it is, but Pokémon's on a whole 'nother level.

I can see the two games being comparable in terms of "core" backlash, but I don't see Game Freak changing course to save face the way Sega did with Sonic, as they simply don't need to. (Unfortunately)

Eh… call me a bootlicker for GameFreak, but recent leaks have shown a lot of promise (e.g. GameFreak responding to the controversy of BDSP by claiming that simple remasters are no longer sufficient, full remakes are the future; upcoming projects seem very promising, creating an entirely new engine and everything), and Z-A has been praised very highly — and rightfully so — by core fans of the franchise (though the general audience has not let go of SwSh+BDSP+ScVi).

I'll believe it when I see it; I'm still sceptical that Gamefreak will raise their standards when releases as technically poor as the last few continue to sell like crack, but I do hope I'm wrong.

Yeah, Pokémon is unstoppable at this point. They can release anything and it's going to sell 20m+

On the other hand even if the Sonic games never sell as well as Pokémon the fact it's still alive nowadays with a record selling game (Frontiers) is a miracle. Releasing anything as bad as 2006 can kill your IP if your fanbase isn't as passionate as the Sonic fans.

I know where your getting at, but the difference is even if Sonic 06 had it's bugs fixed it still would have been an average 5/10 game. Pokemon S/V is a good game that launched in a bad state.

My naivety could be deceiving me to be honest. I’m staying optimistic. Again, I still think Z-A was a pretty darn good release! Huge step up over all Switch releases from everything I’ve heard (and I’ve prolly listened to at least a dozen reviews at this point).

I hope you're right.

I also hope it didn't come across like I was shooting down your OP, I actually think you make a good point.