full series spoilers (including occultic;nine@Archivist the thin of it is
we learn in A;C that the "player" gives pollon the ability to save/load, which based on descriptions from those around him, and himself, is very similar to reading;steiner/time leap, in function, albeit more developed.
we know that all main characters are observed by the "player" via the load regions. and we know that okabe is not a gigalomaniac, and thus his power was not derived from such phenomena, so okabes reading;steiner must be an earlier attempt by the "player" at this lesser developed ability.
full series spoilers (including occultic;nine@nellePoint now that I think about it, okabe's ability technically exists in all timelines despite being prototyped in a single one of which we know divergences happened before that point, as we see in the movie. So your hypothesis is pretty solid, it being like a prototype copy-pasted in many variants of the similation
full series spoilers (including occultic;nine@Archivist the main issue with this theory is the propensity for others to have (albeit much weaker) reading;steiner, the closer they are in relation to variation events.
so id probably have to modify the theory to say the observer hightened his attenuation to the phenomenon and then used the "glitch" in reality/the earth machines, to give pollon his abilities.
although that falls apart further so when you realize that the reason okabe has such strong reading;steiner is likely actually due to him being the absolute center of time travel shenanigans and its always somehow related to him. which then forces me to modify it with just "observer gives pollon abilities based on what the observer understands about the mechanics of the world, a hack, if you will."
full series spoilers (including occultic;nine@nellePoint wait, that is consistent with the Noah machine and the monopole generator of Robotic;Notes. The monopoles are not supposed to exist in the simulation, but they used a glitch by making the main character observed and using perception alteration abilities and machines to create them. Would that not kinda make Akiho and Kaito artificial gigalomaniacs?
full series spoilers (including occultic;nine@Archivist they are actually artificial gigalomaniacs, their "conditions" arose from an accident on a ship which was testing of an early noah 4 prototype, which later a full version is used.
we know from ch;n and ch;ch that such events can create gigalomaniacs