Hmmm. That's a strong argument provided someone actually reaches those levels. That doesn't fully counter the argument that having constraints on infrastructure purchases (i'm not thinking 100 infra per day or anything abysmal like that) would be a valid way of addressing the issue.
If there are individuals who are trying to break the game then I'm more in favor of having them banned from the game than having game mechanics that might end up causing problems themselves.
If one day in the future I want to send a few million to a new guy as part of a growth loan, I'd like to freely do that at my own digression, and not be limited to some miniscule number.
I'm in favor of eventually having alliance-driven aid programs that enable new players to have one thousand infrastructure in a new city, provided it becomes possible from multiple alliances, and provided more interesting aspects related to infrastructure and/or population levels are introduced by sheepy in the future.
What I'm not in favor of is having 20k infrastructure in a new guy's first city. You say having aid caps would solve that, I say having infrastructure purchasing limits (maybe something like 100 per city +400, per day) would be an acceptable limiter.
Anyways, why not also propose a limit on trades too? If they wanted to, they could send 5000 steel for 1 dollar to a new nation and they then sell it all as a work around to the aid limit?