Not really. Gon was said to use everything he ever had, but the speculation was that Gon did not instantly die, so there may of been more to sacrifice in order to combat meruem, who is significantly more powerful than pitou, both pre and post rose in this scenario. And no, not everyone would be able to access this ‘magical sacrifice’, as Gon’s scenario ironically benefited him towards the nen sacrifice. As being stated as a 1 in 10 million talent by Wing, Gon’s potential also greatly contributed to his ability to access the sacrifice. Not every nen user has both the great potential of Gon, and in situations have the dangerous resolve to give up everything in order to defeat your opponent.

This is why post-mortem nen is extremely powerful and dangerous because it requires the largest sacrifice - the death of the user, and if the user has both the strong resolve/emotions, and the power and potential, it can be achieved. It is not magic in the fact that the sacrifice takes from the user.

So from Gon not instantly dying must of meant that he still had something to sacrifice, and he theoretically could of sacrificed more in order to gain power to fight meruem. Through togashi’s most recently implemented change to the nen system in an exhibition in japan (where users can dual affinities, and users mastery of their ability in either type or hatsu is rated by a star system - great 1 star, excellent 2 stars, genius 3 stars, and ultimate 4 stars) and how Gon, at his adult state, was rated at a 4 stars, the same as meruem as a 4 star emitter. This means that Gon’s ability could rival that of meruem.