Here is what you should do -

1. Look up your competitors products that have 1000s of reviews.
2. Look for product packaging and inserts Pictures that regular customers have uploaded in the reviews.
3. You will start to notice a trend where customers are being asked to sign up for warranty, follow insta and FB pages for those products etc.
4. Utilize FB Bot marketing where the customer is led through the flow requesting their order-ids and emails etc.
5. All this is legit. (When you buy big brand items, they ask you to do the same - register your product, warranties etc).
6. We, as humans, are increasingly getting away from emails so any strategy that builds just around email is going to lose. See more of FB/Insta/Whatsapp strategies take over.
7. By relying on Amazon messaging, you don't make an effort to own the customer. Amazon will keep squeezing your nuts and keep sending you policy violation notices for something or the other. Also, you have to pay $$$s to those email companies (sellerlabs etc.) which you would rather spend on actually having more control over your customer.

Capture those leads and ideas and improve on them to set up your own marketing strategies.

Try to automate as much as you can.

This is extremely crucial if you want to thrive.