Globally, Kobo has around 10% market share for ereaders. If they gain another 5% of the market, that's a 50% surge for them and around an 8% drop for Amazon.

In the end, it probably doesn't really matter. All the profits are in the books themselves and there are reports that Amazon is doing alright there as well. That said, global ebook sales are still down from their 2013 peak.

https://www.ereadersforum.com/threads/amazons-global-dominan...