A JSON-LD for SEO customer was planning their product organization last week and were questioning if they should use a product for each style or if they should group them and use variants.
It all depends on how different they are and how much unique content each variant of a product will have. If there'll be a significant amount of different copy for one style another style, then having each one on their own page would make sense.
If the only difference are the compatibility and specs (e.g. sizes), then Google might consider all three of those products to be the same. They'll then pick one to use and flag the rest of them as duplicate content while hiding them in the search results.
My rule of thumb is to consider how you'd organize shirts:
- a t-shirt is a very different product than a long-sleeve shirt, so they should be separate products.
- a red t-shirt isn't significantly different than a blue one, so they should be the same product but with a variant for colors.
- a large t-shirt isn't significantly different than a small one, so sizes too should be the same product but with a variant for sizes.
- a crew neck t-shirt might be different than a v-neck one, so those could be separate products but you could also use variants for them if you want (cut variant option).
If it makes sense to how a customer would shop for a product, then that's how it should be organized.
This will also store-specific.
A high end store might have each shirt color as a different product because that's how their customers buy and they have custom descriptions around the color.
A mass merchandiser (like Amazon) might use one product for all shirts and a ton of variants to let a customer drill down into one. What makes sense for them might not make sense for smaller stores.
One SEO feature that actually works well is structured data.
Mostly because the data helps Google's algorithm which makes their job easier.
You can either audit, code, and test your store's structured data by hand or install JSON-LD for SEO and have the structured data you need for several types of Rich Results.
It's already helped a few thousand Shopify stores with their structured data and it could help you too.