It is still bound by space and time. The fact that the Chaos Force is the only realm outside of both should tell you all lower realms are beholden to them.
It's never been stated to be operating within it's own space-time compared to the game version. While they're similar in many ways, the Archie Continuity opeartes entirely on a different scale dimensionally and space-time wise.
This is your confusion here. Time isn't the 4th dimension, it's just a direction of progression upon an object. A realm can have 4 spatial dimensions and a time dimensions to be 5D, it can have 3 spatial dimensions and 2 time dimensions and be 5D and it can have just 5 progressively superior dimensions to be 5D.
Alright......
Maginaryworld and NE are bigger than the lower realms but are still spatial in nature and still operate within a temporal axis. The Chaos Force is the only realm outside of both which is why Solaris would be physically below it despite being bigger than NE.
How exactly do they operate within a temporal axis when they're shown that space-time is either being producing on an uncountable infinite scale along with time being irrelevant? With those in mind, they can't operate within the confinds of space-time.
It doesn't. Time being irrelevant can be solely due to time being fluid in that realm or the people in that realm being Immortal.
Time being fluid? Time is irrelevant within that plane of existence. How can it be fluid? Time isn't stagnant either since it's irrelevant. If anything, it being irrelevant in this case means it's outside the confinds of space-time.
Who said they didn't or didn't try to? As the other user mentioned Solaris is literally one page in a companion guidebook. It can be strong without breaking the setting.
We're contrasting Archie's continuity of Solaris with the Game version since that is where the most information is present for Solaris. While they're both extremely similar, they're arguably not the exact same in terms of cosmology and dimensionality wise. Considering that in 06 he was consuming all existing timelines where time would collapse, this would include Maginaryworld since in the game cosmology, Maginaryworld is considered have a 4D structure within its realm. That was really it in terms of cosmology at the time within the games. Within the Archie Continuity, it's a different story since multiple higher dimensions are now present. Hence, he scale Solaris to what he was going to consume within the games compared to just the Archie Continutiy. That means, the Next Evolution and the Chaos Force would be left out of it. Even if you don't want to argue it like that, we see that in previous instances, we see that the Ancient Walkers have had to step in with these cosmological threats that threatened the existence of the Next Evolution and the Chaos Force. With the case of Solaris, we don't know if he even tried to do so. What we can infer is that within the games, he tried absorbing the multiverse plus Maginaryworld and nothing more than that. Given Solaris' description within the Archie continuity, we see he was defeated in a very similar way as he was in 06 with no Chaos Force deities and/or anything involving the Next Evolution being present. Hence, we can't scale Solaris equal or above the Next Evolution and/or the Chaos Force.
Also all the Ancient Walkers are dead by Solaris. It's the Neo Walkers at this point.
If the Neo Walkers took the place as the Ancient Walkers in terms of duties and power, then they would be the ones to get involved as the Ancient Walkers did previously.
He can contain NE without being qualitatively superior.
He cannot contain the Next Evolution due to being a lower dimensional tier.