The search algorithm on eBay is a total nightmare if you are in the UK. Random results unrelated to your initial search show up in their hundreds, as well low value items from Chinese sellers. It is positively discouraging to buy from eBay, especially on the app which is what most use.  And the so-called 'filters' are time consuming and fiddly to use. Even after applying filters you're left with items totally unrelated to your original search. I am sure people give up and try another platform. Contrast this to Vinted which is an absolute pleasure to use as a buyer. Their search is super effective and really easy to use - finding the items that you want as well other related items based on your initial search. I've bought more from Vinted than I expected to because they make it so easy to find items that I love.

eBay's search is a mess and I actually think this is a major reason for their declining sales in the UK.