SEO is developing as all in our life... early we didn't have Internet and it was so difficult to tell everybody what you want to tell
SEO is not getting harder, It's just a cause of increasing competition of that keywords which we select to get top positions on search engine.
Search Engine Optimization being a competitive industry has gotten tougher over the years not only because of increased competition, but because Google has been on their toes trying to discount any shenanigans that people in the industry might be up to.
I don't think it's become a nightmare for webmasters, but rather a challenge. Search engines are now looking for quality and that helps to make the internet a more information-rich and credible source.
SEO is become one of the most important part of business strategy to increase the business so the SEO become tough day by day........