Adobe products are still the industry standards. It is highly likely during your career that you will need to submit source files from Illustrator or Photoshop at some point. If all your clients want Adobe files then it is beneficial for you to learn the basics for any client projects that require a source deliverable.

Having said that, a tool is a tool. If you are comfortable and efficient using Sketch then keep going at it. There's no reason to hamper your workflow by worrying about what to use. If your main concern is a beautiful and efficient end design, then continue on with Sketch.

I have used both extensively, but tend to use Photoshop 9 times out of 10 so I can work with colleagues. Bear this in mind too!

If you know how to use Sketch already, then it shouldn't take you long to get a basic understanding of Photoshop. Most of the tools are transferable.

Design software uses the same terminology: filling, strokes, slicing, alignment, etc. It's just a matter of learning where the tools are and this can be accomplished very quickly.

Using sketch won't necessarily put you at a disadvantage, but it's not a bad idea to learn the basics of industry standard tools.

Yes, and learn InDesign while you're at it. Who knows, one day you might have to layout a book, magazine, or other ancient print materials.

I am in a similar situation where I am very comfortable in Sketch and feel out of place in Adobe products. In a class I'm taking "Layout & Typography" the instructor uses Illustrator and bases his classes/assignments around trying to get students familiar with the Illustrator workflow. I expected to be completely hindered by this software but Im actually blown away.

There are some features which do not even come close to existing in the Sketch world and would require me to spend a lot of time to achieve the same in Sketch. For example, my latest project is a brochure which has three panels of text. Illustrator lets you "connect" these things so they overflow onto the next panel.

I actually recommend you spend the time to learn it. As you carry on in Design school, you will definitely come across assignments/projects that depend on certain features of Photoshop and Illustrator. I suggest you start learning from right now, so you don't fall behind.

If you can complete your assignments with Sketch, that's great. I wouldn't limit myself to just using Sketch, though. It just doesn't offer all the capabilities that Ai does, and at some point your work will be limited. That is, unless you are just doing web/print design stuff rather than digital illustration. It's like using a 16 color box of crayon vs. 96 colors box.

If you want to use something other than Adobe (yay!), check out Affinity Designer, or CorelDRAW. I've never used either, CorelDRAW has been around for years, and although Affinity is new, it looks like it is much more tailored to illustration than Sketch is.

I'd like to compare learning the Adobe suite to going to college. It's expensive, you don't need it, but it is really going to help you get a job. I want to tell everyone to join the revolution and not go to college/buy Adobe products, but the reality is that isn't quite possible yet (especially is larger, more established companies).

At school, you have the benefit of being able to start your own projects. Once you get a job, you'll have to adapt, complete and maintain designs that were created by other designers, which are most likely created in Adobe products.

You may also find yourself working at a place that only has Adobe products. Possibly even on Windows.

Learn enough to be comfortable with Photoshop and Illustrator. If you know Sketch, you'll pick it up soon enough.

While it's good to know what the industry is using, I also believe that designers should more actively push their tool of choice wherever they work, if that means working faster/better.

Pushing new & more efficient tools is quite common on the development side, don't be afraid to do the same! :-)

I had a hard time believing this was a serious question.

It's still entirely necessary to be proficient in Illustrator and Photoshop. The main problem (in my eyes, at least) that's keeping Sketch from becoming even remotely standard for this industry is that nobody knows if the application will still be around in a year, yet alone in five or ten. This means that using it for long-term work on sustainable products might lead to loss of work if the file format ever ceases to be supported.