I think that 2 is correct. Grammarly also indicates that 2 is correct. However, according to @Chungoli, 1 is correct.
Who is actually correct in this scenario?
Chungoli's comment to the question you linked is correct, but it doesn't apply to your example. Let's look at the example from the linked question (a bit simplified):
Succeeding in college is often a challenge for students.
Here, you're referring to "college" in a more abstract sense. You're not talking about any individual school or any individual schools, but about the "idea of college" or "the principle of college", so to speak. You might also say, you're referring to a whole sector of the educational system. For this use, you have to use "college" in singular.
You may also want to note that there isn't a determiner, like "Succeeding in a college" or "succeeding in this college". This is also typical for using the noun in a more abstract sense.
On the other hand, in your example
Most colleges provide services designed to help students.
you are referring to actual, individual schools. Some of those provide the services, some don't. You're talking about multiple colleges and therefore have to use the plural.
In this case it is plural - "most" as it suggests more than half of many colleges, so you use "colleges" plural form.
The ones he gave have "majority of students" which is singular as it is a collective noun so "college" is used. "None of them" is also singular.
