Tbh this actually seems like the only viable choice to me.
Without dedicated support staff and fraud prevention like commercial solutions might be able to offer, I don't think online sales are possible in any safe way without simply trusting the other person.
So the platform is best used just for local in person sales (like on a flea market).
I've used forums for this purpose and never had an issue with 3d party payment, however it also had a reputation system, which this seemingly doesn't have. There are also only 17 items up at total in "All", a decent part of which are not real items (like the EU flag up for sale for 8000 billion euro) and services (company selling logo's for 30k with an AI generated image as example).
Denmark has dba, den blå avis (used to be a news paper of sorts where you could trade). Owned by ebay. We also have a bunch of other services like Reshopper for everything baby related and gul og gratis which paradoxically is neither gul (yellow) nor gratis.
In Romania, Poland and a few other territories there's OLX.
It's weird that this is the one corporate, monetized online thing that hasn't gone global. Even for car rides Uber is in most markets even if there's a side alternative.
I guess eBay is that, but it's just residual in most places, you mostly get hits from anglophone countries.
It has gone global but not in branding. If you search some of the names mentioned in the comments here, you´ll find that many are owned by a single company.
Both LeBonCoin and Wallapop have shipping integrated into the platform. Of course some sellers turn it off which is annoying but you can do most things without meeting a human.
There is second hand shops and facebook marketplace is pretty common. In warmer season, we have "brocante" and "vide-grenier" something like a mix btw a garage sale and a local market. I usually put the things I want to give in a box and call my friend to check on it. For close I send a bag to a friend or neighbour, I know they will pick what they want and give the bag to someone else.