Sure, but we're not talking about
that much more people and we're not talking about more than the city has, historically been able to accommodate.
As of 2020, the city had about 58,000 people. As recently as 2000, it had 65,000:
en.wikipedia.org
In 1940, it had over 70,000:
typed overview of Springfield as a desirable location for business and industry
archives.ccplohio.org
I didn't bother finding anything between 1940 and 2000, but if my experience elsewhere in the rust belt is any indication, the population was probably pretty steady throughout that period. I'd guess that it peaked a bit higher than that in the 60's or 70's and then started turning down in the 80's or early 90's.
The estimates I've seen for the number of Haitians who've moved to the city is between 12-15,000. Even if we assume that none of them were counted in the 2020 census (which is probably mostly correct, but not entirely correct), that would still only put the total number of people up around the 70,000 mark that the city managed to accommodate for most of the second half of the 20th century. Yes, there's going to be some strain, but it's not an insurmountable problem. You already have the roads and sewers, and most of the buildings and other utilities you need. You probably need help with labor-intensive services like hospitals and schools. It'll take work, but it's doable.