Well, not quite in that way. Survival of the fittest doesn't literally mean 'survival of those with the most physical strength'. It means survival of those most well adapted to their environment, intelligence included.
And evolution hasn't effectively halted either. It's hard to tell that sure (because evolution on a massively noticeable level is a slow process and human history is short) but the whole process of genetic mutations arising and people doing better because those mutations make them slightly better for their environment is still going on.
And the traits selected for aren't random nor a crapshoot, they're just kind of overshadowed by social situations and hierarchies. If there were two kids from the exact same background and one was 'more intelligent' than the other, the more intelligent one might do better. But it's very rarely that simple in society now.
And evolution hasn't effectively halted either. It's hard to tell that sure (because evolution on a massively noticeable level is a slow process and human history is short) but the whole process of genetic mutations arising and people doing better because those mutations make them slightly better for their environment is still going on.
And the traits selected for aren't random nor a crapshoot, they're just kind of overshadowed by social situations and hierarchies. If there were two kids from the exact same background and one was 'more intelligent' than the other, the more intelligent one might do better. But it's very rarely that simple in society now.