As MrLeeB said, users may not be able to find what they're looking for and there would likely be some unnecessary wasting of "crawl budget", which could have an negative impact on indexation and rankings.
As Mike R. said, it would probably be terrible for the user-experience, and thus rankings and conversion rates, if you had too many categories.
For many years eCommerce businesses have built out category pages based on internal-searches performed by visitors, as well as the keywords they used to find the site on search engines. When used sparingly, this strategy can help inform the category structure of the site while offering a landing page for high-value keywords.
It can help copywriters understand which pain points and questions are trying to be solved, thus which should be called-out as benefits of the products within the category. It can even inform which products you source or develop to sell.
When abused, like when software, website code or database logic automates the process of creating these pages, the results can be devastating to the business.
After a few months of long-tail growth, the site may experience a major ranking loss across the entire domain for all but clearly branded and hyper-long-tail searches. If you are in the game of burn-n-churn, it might work for you provided you pay for some seed-traffic to build out the keyword lists.
...just in case you were thinking down that path.