Hank here from Shopify!
The variant limit cannot be increased natively within the admin, but there are other options for you which should be of benefit to you.
You can split one product up into several separate products and so increase the number of available variants per product.
So say you have a product like something that is made from different materials (wood, metal, plastic), you could make three different products for the three different options. That way you could then have up to 100 variants per option. the same applies to items of clothing, you could create the product in different colors, etc.
Outside of the admin, there are some third-party apps that can also help you with this. I will list some for you below.
Let me know if you have any further questions!
All the best,