There are definitely at least two camps. I know people who think Photoshop is it, and people who have no use for Adobe but think GIMP is best. There are also many who are considering migrating since Adobe announced their move to a subscription billing model. Paint Shop Pro is sometimes advocated too. Businesses pay for software with pre-tax dollars, so it will be interesting to see how it all works out.
I haven’t learned enough of GIMP to use it efficiently but I have seen others use it to do all the same editing I do with Photoshop. It has the power and requires the same effort to learn.