Late to the party here, but I’ll give my experience regarding this question.
If by “learning a testing career” you mean manual testing, then I would say yes, it’s relatively easy, particularly if you are a millennial or younger like myself. That’s because we grew up immersed in application usage, and can easily tell a broken app from a solid one, and can more easily think of ways to abuse/break the app if so inclined. Not to say that if you aren’t in this demographic that it would be harder, as long as you’re somewhat tech-savvy.
If instead you mean automated testing, you have to have the manual experience plus programming skills, which of course takes way more time to learn. Relative to other software development “flavors”, in my experience, it isn’t any more or less easy or difficult to learn, it just takes time like anything else. There are so many specializations in the software development world, and test automation is just one of them (and also the most fun one, in my humble opinion
).
One unique challenge for automated test development that you absolutely, 100%, without exception, MUST master is how to future-proof your code, arguably more than any other subgenre of software development. This is because you are writing code that essentially mirrors the application you are testing, and if that application is undergoing rapid development, your test code will break just as fast unless you are smart about it’s implementation. This is why it’s so important to follow patterns like the Page Object model to keep your scripts healthy and to keep your maintenance costs within reasonable limits. If you are lazy and use things like recording software as your way to “develop” scripts, you are in for a world of hurt and will end up spending way more time maintaining your test code instead of adding to/improving it. This is what truly sets the boys/girls apart from the men/women, and the engineers from the testers.
There are many more challenges unique to this career, obviously, and even within this branch of development there are so many ways you can take your learning and specializations to follow. Do you want to focus more on behavior-driven design (BDD), test-driven design (TDD), data-driven testing, etc.? Which technologies do you want to use in your stack? What type(s) of applications are you testing? This is where I think Katalon is great for both experienced and new testers, it can accommodate all of these in one tool.
Anyway, I could probably go on and write a novel on this subject. I’m actually in the middle of developing an entire set of learning modules for this career path that should be available on one or more of the popular learning platforms out there within a year or so. I’ll link it when I get around to finishing it 
Cheers!