An interesting question. Very interesting indeed. Thank you very much for asking that one. I've come up with some explanations, mostly conjectures, but that I hope with time can be proved and based on solid lore.
One possibility is that the answer would lie first in what Malak meant with those words. It could be that, after so much effort, all aimed at becoming a great Dark Lord of the Sith with rule over the galaxy, Malak saw, at the moment of his death, that he had failed. His name would never be remembered as he would have wanted and he would sink in the darkness of death and forgetfulness. He'd become nothing but a memory with no legacy. Revan understood that, at the moment of his own 'death'. For his plan to work, he would have to disappear long enough to the Dark Council not foresee his true intentions. He would have to descend into darkness, much like his old friend, but with one huge difference. Revan would have achieved his goals, and his legacy would be felt through the galaxy. In this case, his speech at the Foundry would have been some kind of a joke to himself.
The second possibility is that his words were not directed at the strike team, but at the one who was commanding them. It is true that the Empire's strike team would not see meaning on those words, but to the Emperor, that would not be the case. He knew Revan and Malak well, and it would not be hard to see the meaning of that speech with only such knowledge. Even if the Emperor had not cracked Malak's last moments from Revan's mind in the 300 years he had to do it (though his success in doing it is also possibility), it would not be hard to connect the dots. If such was the case, if Revan's 'last speech' was directed to the Emperor, it would only be part of the bluff. The intention here would be to give even more credibility to his 'death', since the Emperor would also think: 'why would he say this as anything other than a final lament'.
The third possibility is that those words meant something to Revan himself, and by doing so, they would mean something to the force sensitive on strike team. It is common knowledge that the Force can be used to read the thoughts of a person. But it is also common knowledge that these thoughts can be masked with other thoughts, or even force techniques. So the speech here, in this case, with all the memories and emotions attached to it, would work as part of a barrier to all Revan was really thinking at the time of his 'death'.
The forth possibility, and the most interesting one, is that Revan, in his genius, used the speech to accomplish all three above. Well, who knows? Let's not underestimate the guy...
Of course, that there is also the sad event that Revan died after the moment of his speech (which I strongly disbelieve). But even if that is true (which I, again, strongly disbelieve), the whole theory could not be discredited. In fact, only the last part would. If Revan died, it would surely be an intentional and planned death. A sacrifice so that the Foundry could pass to the hands of the Empire and become a centre of discord.
The truth though, and what might have happened in reality is that Bioware did put the speech in the original Foundry and, not noticing all of its implications, maintained it after they changed the mission. But such fact would be irrelevant for the lore, and there are dozens of such mistakes in Star Wars universe that later were incorporated by canon. So let's live off the land.
Hope you all liked it, and found the explanations satisfactory.
To those that believe that Revan is still alive, some help would be really appreciated.
May the Force be with you.