Let me share my story.
It all began on eBay - 2015. Started an eBay shop selling a myriad of things - kitchen, office, clothing, whatever. No niche - just a shop with anything in it. Got sales here and there. But, the surprising product that kept selling was unexpected. Sorry, can't share what it is but it is in the tech category. Started out as a sale a day, then a couple more, until later on I was just earning an extra $5k NET per month - the earnings paid for my car, majority went in to the "side business" to circulate the money.
These products were dropshipped - no inventory.
The sad story? It was from AliExpress - so I got dinged on shipment times and the tracking numbers (US-based).
BANNED. FOREVER. Bye bye $5k/month.
The moral of the story? Do your research. Find good trustworthy companies or collaborate with smaller companies - but the risk with smaller companies is that they could just be middlemen.
Build your own site and utilize SEO. Niche down.
Again, lots of work but doable.
The caveat - people are impatient and with dropshipping, shipment takes ages especially if it's coming from China. So, either you dropship or you build your own brand through Alibaba (costly).
Is AliExpress a good dropship route? Yes - if you find good sellers and if your customers are ok with long shipment times. You have to let the customer know how long it will take for them to get the product they ordered or they will contact you and be unhappy with your service and ask for refunds. If they do, make sure you refund them. Otherwise, you'll fail.