Honestly I haven't read or researched St. Malachy to know of him other than his prediction of the last pope. As far as Nostradamus his predictions are so vague and have been interpreted by so many, that they are not all in agreement.
The only thing that I do find interesting is both correlated this pope (at least I believe it is this pope) as the last, signaling the end of times; but the phrase "end of times" itself could be interpreted differently or signify an end of something else.
Nostradamus can be rejected on its face - It is too vague to be of any worth. And then the quatrains were intentionally mixed up on purpose to hide their intent - That's alright, but without the key to their order, it's just mix-and-match any which way to get what you want. Seriously, a magic eight ball would hold more prophetic weight.
The most significant thing about Malachy is that his prophecy was purported to have been lost for several hundred years, being 'rediscovered' many years later. That means, if true, that at least the early part of the list of popes would be without any machination... The early popes already were done by the time the document was found. Like I said, if true, that might lend it some credence. But one cannot confirm or deny that part.

What is a far more fruitful study to me is the prophecies found among the Dead Sea Scrolls. They have some stunning revelations and come from within the service of YHWH. I really do think that Qumran was the fabled 'School of the Prophets', and not an Essene encampment at all. It is a tremendous study, especially in the field of eschatology, and in proper dating - Just the study of their calendar in the light of their predictions is uncanny, and opens a huge realm of knowledge surrounding the shmittah/jubilee and how it can be expanded into calculations - Something I have long suspected in my study of Daniel.
In the end, I would say that the 'End Times' have been going on a very long time - Since perhaps the resurrection, and almost certainly since the destruction of the Temple. People can't see because they do not pan back enough. This stuff has been going on for two, almost three ages. But that is not the same thing as the 'Time of the End'... THAT is coming. We are in the transition just before the end of the final age, the last Jubilee approaches, ushering in the age of Messiah.
That means it's still a ways off, but careful - It all has to be done BEFORE the new age is ushered in... Many things must occur before the fact, just as Yeshua came before that age was all done -right in the last years, ushering in the predicted age of Grace (predicted by those at Qumran), typically noted as entering at the destruction of the Temple, and the diaspora at that time.
That new age is here... The final Jubilee begins by 2035/2050 at the latest... Fifty years to go by that time. And it could be earlier, depending upon which timing convention you use. Not to mention Yeshua said it would be cut short, or no man would survive it.
So yes - The 'Time of the End' draws nigh.