Yes I think this season is mostly done for Ajax Amsterdam as they are also eliminated from the KNVB Cup and even if I weren't to assert that miracles are not impossible, I think it is impossible for Ajax Amsterdam to catch up with PSV. But I think that PSV themselves are quite shocked after they gave away their first points in the Eredivisie and right after that game got eliminated from the KNVB Cup themselves. This is certainly bad for any plans they had.
I don't know what Ajax Amsterdam is aiming for, but the biggest of all possible goals would be to catch up with Feyenoord. Ajax has one more game to play against them in the Eredivisie and apart from that can only hope for Feyenoord to drop points.
They've got players no doubt but the squad needs to be better, Ajax is a team better than a narrow win, at the moment though, finding the right player who's top and ready in all areas to give that competitive capacity in both the domestic league and the European leagues will be hard. Every team won't want to loose their kept men and every player that's be free are the ones that weren't so solid for the team.
It's quite expensive to get for a team a high valued player no doubt and Ajax management may not likely be up to the task and it's going to be unsafe to settle for a less standard player. Their inconsistency is unhealthy and they just have to find a way to stop the wins from occuring through a narrow means. The coach is good at what he does but he has to improve himself and the team too, once all the necessary characteristics needed are in place, then it'll be an easy ride for Ajax.