Napoli basically just made sure that Atalanta doesn't win the league this season. Obviously there are so many games left, so anything could happen still, but I do not think that there will be such a drastic change that Napoli and Inter both starts to lose games or get many draws while Atalanta keeps winning, that's unlikely.
Obviously Inter could still catch up to Napoli, that chance is there, but Napoli at least looks great, while they played more games, they have enough points gap too, so that means Inter has no chance but to win those games, not even a draw would be okay. Winning this game was a huge huge step for Napoli for their league title hopes, and they did exactly what they needed, this was definitely amazing for them.
Napoli really tried hard to stop Atalanta's steps in competing for the title this season. In their meeting in week 21, Atalanta actually played quite well, but unfortunately they lost consistency towards the end of the match which made Atalanta lose points in this match.
Lately Atalanta seems to have difficulty getting a win, they have drawn in 3 consecutive matches and lost points when facing Napoli.
Regarding Inter Milan, it is very unfortunate that they were only able to get a draw when facing Bologna, so they were only able to collect one point. So that the points obtained by Inter are again far behind Napoli.
and in the meantime Inter will soon face Empoli, hopefully they can get better results in this match and get 3 full points, so that Inter can reduce the difference in points with Napoli.