Like everything else, it depends. Cybersecurity is very diverse. The language you choose will depend on what you choose to specialise in. If you like the mobile space and want to pen test mobile devices, it is a good idea to know java, or Kotlin for android and for iOS, swift.
If you wish to get into bug bounty, you may need to know a lot of assembly and some software development principles.
If you wish to get into OS pen testing, you need to understand low level languages like c, cpp and objective c. You also meed to know how operating systems work at a low level. Malware like Meltdown and Spector rely on some OS and hardware weeknesses.
It would also help to know comand line commands for the platform you wish to pen test,e.g. bash on Linux This will enable you to write programs that do these commands in the background without alerting the user.
Teddy Okello, thank you! I would like to talk with you more on this subject please, if you have time. you sound pretty knowledgeable and I have absolutely no one to ask these questions of. I can give you my personal number if I need to.