Or shall I leave it there and go for something else?
If no one ever did something because "a lot of others are already doing it" there'd never be any new musicians, writers, artists... etc.
Anyone may excel at anything pushing them ahead of the "tons of others" already doing the same things.
Whether or not something is worth your time is for you to decide. However, traditionally, "others are already doing it" is not good reason to not do something.
In terms of financial return, well, then it all depends on how adept, comfortable, and proficient you are with something and how quickly you expect to make a return. In a saturated market, even if your kung fu is strong, it may take awhile before you can make headway. However, if your expectations are realistic, there's no reason to not move ahead with something which interests you. Every day you delay is a delay in returns.
Any end that help you or is part of your job is worth learning, don't be those who think if a language is dead then you don't need to look at it. Be the one that outrun them by knowing that "dead" language, maybe made you understand the tasks in hand and future solutions.
When you know different parts that make a complete product, you will make your part better, faster and more rewarding.