Nothing he's done so far will alter the fact that people will produce garbage which will need to be removed somehow, so the market for the garbage collection is still there, and there's no reason to suspect any of his actions so far will cause people to be more wary of garbage collectors so the information gathering aspect is still entirely plausible. You may argue that for some reason the guy wouldn't notice the opportunity now, but he can suggest it if necessary so that's not really a factor either.
The quality of his work has likely spread throughout the city, if not farther, and just as likely caused the citizen's expectations of garbage disposal workers' work to be increased. This in turn will have likely caused him, and the other garbage disposal workers, to get much more attention than they used to get, and probably not always the good kind of attention, as the other garbage disposal workers will probably have been expected to perform as good as the MC, and this will likely have lead to resentment.
Now, with the recent kidnapping experience, and his role in it, he will probably come to find himself with even more attention than ever before, and if he ends up becoming a sort of small hero in the eyes of the citizens, this could also lead to an increased attention on him, his work, and the other disposal workers as a whole.
All of this is directly against his goal of having his employer create the information network in this timeline, too, and get himself involved in it once it is created, because the increased attention makes it harder to snoop on people's private conversations, and the resentment from the other workers will make them far less inclined to help the MC or the boss out by giving information, at least not without a hefty "rewards" fee attached to any information, which would negate the point of running an information network.
Now he's planning on taking on even more routes himself, either putting 6 other workers out of their jobs - in which case, he would have created 6 enemies, and even more attention to himself and his boss for allowing it to happen, - or they get forced to quit or move to a new location after the expansion. The expansion which will increase their company's and worker's attention even more, by the way.
So, I don't know how anyone could claim that the MC hasn't done anything that could alter the timeline's events, when all he has done is alter the timeline's events.