Marketplace vs tour operator
Marketplace: you can see who your guide is, what they are certified in, and read their own description of the route before you book. The guide sets the itinerary and price.
Operator: the itinerary is standardised and the guide is often assigned late, so you book the brand rather than the person.
What to compare
Whether certifications are verified and displayed, how much of the price reaches the guide, whether cancellation terms are visible before booking, and whether you can contact the guide with questions beforehand.
Related questions
Do marketplaces cost more than booking a guide directly?
Not necessarily. Guides set their own prices, and the platform fee is normally a small percentage rather than the operator margin a packaged trip carries.