Marktplaats is not an auction place, it is a market place (kind of like Craigslist). They never changed that, and eBay Netherlands has always remained a niche.
You can also do auctions on Marktplaats, though it's much more freeform than eBay. I auctioned a 1980s Transformers toy there ages ago, and I got such weird vibes from the two top bidders that I was happy to sell to a third bidder that showed up.
My pet theory is that eBay acquires/operates classified marketplaces and lets them dominate enough to prevent a competitor from appearing and taking marketshare from the more profitable eBay platform.
