It depends on whom you ask.
I would say yes, insofar as what can be learned from books is concerned. To learn well some form of mentoring or apprenticeship is required though.
The necessary knowledge, guidelines, and annotated examples are now published in books by competent contemporary astrologers. There is no need to suffer old English, unless you like old English, suffering or both, of course.
Plus, it is important to note that many mistakes committed to ink in the 17th century have now been corrected by some bright minds in the contemporary Traditional Astrology community. Both astrological technique errors and usage errors of terms that have different meanings depending on the time in history they are used.
Conversely, these corrections are avoided and rejected by many stubborn living traditional astrologers. So, these highly conservative astrologers probably do not agree that horary can be learned by means other than repeating the content of old books without any analytical thought to support it or refute it.
A genuine interest in our history and passion for knowledge is admirable and deserves respect. Scholars must have fun too; I would not want to stop them from collecting information.
However, caution is advised about becoming reliant on old books at the expense of common sense, which can become obfuscated by adhering to the common dogma that “traditional” equals “old” and “old” equals “true”.
Studying the old books allows us to appreciate the rich legacy of their authors but by no means is it a necessity to become a proficient horary astrologer.
Horary astrology is still in development. To believe that the complete knowledge of horary and what it can do is already fully laid out in those writings is very limiting.
It hinders the tradition’s natural development. That is an over-melancholic mindset that tends to defeat the deeper and higher purposes of horary, that is to reveal the truth, enlighten, and uncover the obscure.
Let the tradition live and evolve in the minds of the living.
The mind, and thus knowledge, thrive in Air. Only a modicum of Earth is needed to keep our feet on the ground. So, I advise extreme caution when reading books, new or old.
With a few exceptions, as a general guideline, do not take anything as a rule until you have tested it in practice yourself, repeatedly.
As the notorious Mesopotamian astrologer, Marsha Malla said: “The proof is in the pudding”.
Everybody makes mistakes. Living people have the opportunity to correct them in person, in writing, or on video. Dead people do not.
Regardless of which books you prefer, I strongly recommend that you engage an experienced astrologer who also is an experienced teacher whose style you resonate with. This, I emphasize, cannot be replaced by books, YouTube, or websites, if your goal is to become proficient and accurate in your readings.