Don't know if you would be interested in this, but it's essentially about Honkai's immeasurable speed rating and yeah I had similar problems as you back when I didn't know anything related to Subspace Lance. Honestly, thinking about it now. It still should be something that's self evident
Otto stated here that "time" works differently in each realms, it means something realms that probably refer to Imaginary Space, Imaginary Tree and the Sea of Quanta. Obviously this leads me to a question back when I tried to make immeasurable a reality: Does Sirin's attack, if it's outside the realm then it would be linked to the time of that realm? (In which, if it's outside Imaginary Space then it would be linear in nature and not non-linear)
About the arguments presented, it pretty much explains that Sirin's attacks are still non-linear in nature even if it's in different realms. Therefore, Subspace Lance deriving from Imaginary Space in itself shouldn't be a problem in the first place because when it got to Earth. It's still non-linear in nature
Them being a property of Imaginary Space pretty much still makes them non-linear as Imaginary Space is also non-linear in nature and that same attack (as far as I know) derives from it too (
like Sirin's attacks come from Imaginary Space) and the main argument against it would be something that if it's linear in nature when it's outside that place. But in reality, it's still non-linear
Think that's the best how I understand it, for now