It is not. Super Sonic surpassed what The End expected, it is as simple as that. it can read Sonic's mind, it KNOWS exactly how strong it's past enemies are. Unlike Sonic, they aren't a constantly changing data
Late response, but later better than never. With that said-
You're making the assertion that it knows exactly how stronger just because we were told it read Sonic's mind. We don't know the extent to which they did, or if they'd be able to know exactly how strong said opponents are based on reading Sonic's memories. With that said, The End should know exactly how strong Sonic is because they ARE fighting them and receiving live data, and yet still made the assertion all would fall to them. This is just The End overestimating themselves, or underestimating the opponent. If Super Sonic surpassed what The End expected, that just means they underestimated Sonic, thus why they were surprised to begin with despite having live data on Sonic whilst fighting him.
I'll just ignore the "scaling standpoint" because you're wrong, plain and simple. 2-B to 2-B is not a big jump in the Tiering System, in terms of ratio, The End destroys *one infinite snapshot of a temporal dimensional over Solaris". That's a FACT. In Universe gaps are not for us to judge, yes, it's a big gap, but established in canon. What about it?
2-B to 2-B isn't a big jump, I'll admit that, but from an in-universe standpoint and from a scaling (as in Character A > Character B scaling) it is indeed very large. Nor is it "established" in canon outside of a statement made by The End. If there was actual tangible evidence I'd agree with it.
Anyway, if we don't want to accept infinite as hyperbole, there's also the problem of infinite having multiple meanings in and of itself.
Infinite:
"limitless or endless in space, extent, or size;
impossible to measure or calculate."
"very great in amount or degree."
They could simply be stating that compared to all previous adversaries, that their power is impossible to comprehend/measure insinuating a large gap, but not a literal infinite gap in a numerical sense.
Sadly due to how late I responded, I likely won't be able to reply to a reply addressing this comment, but I
should be able to tomorrow.