Hey there! I had these concerns when starting out as well. Is it saturated? Is the market landscape going to shift so much that it becomes too competitive? etc.
The answer is, no. eCommerce will grow year after year for the foreseeable future. Dropshipping is a tried and tested business model that been around for decades and it's not going anywhere. Sometimes the rules change, but the business model does not. For as long as people need to products, eCommerce will prevail!
This is not anecdotal, eCommerce is expected growth into the trillions by 2021 -- Check out this infographic! Staggering numbers. So with that said, don't hesitate to jump into an eCommerce business. Think closely about how you brand your products and who you're planning on selling to, offer quality products that people want and you'll be off to the races!