There are two different kinds of programmers. The ones who went to school and spent some years learning skills like science, maths , physics and algebra, and there are others who learned “coding” to do their day to day jobs. The second group are most likely like learning stuff by themselves, and did not have the opportunity to go to school. Algorithms are done at school most of the time and most of the classes used some kind of programming languages to teach algorithms. That doesn’t mean that self taught programmers don’t know about them but these things can be learned from the books.
So, is it important to know it? yes it is but you can also get a job without them. However, the top 5 silicon valley companies for sure will ask about the algorithms. As a software engineer, i think you should know and have a good knowledge about them.
At the end , algorithms are there to make things better, and when it comes to technology, we talk speed/time and space. Whats the best way and more effecient way to solve a problem. So, yes whatever you do in the tech industry and wherever you are coming from, you need to know the basics of the Big O and other algorithms.
There are companies that made it to the market just because they had smart people to create great algorithms to transfer bits from point A to point B.