OTAs are a scam. They rip off both tourists and hotels.

Always book direct with the hotel. You aren't going to get there and find your room is mythical.

And you never know what you might get. I once booked a "deluxe double" room in a hotel in Tallinn and they just upgraded us to an executive suite for no extra charge for no reason other than because "it was available." I assume it was because we were staying three nights and they probably get a lot of one-two night stays. Availability upgrades (and some of my friends have had them too) are pure luck of the draw, but you only have a chance if you book direct.

Make very, very sure you are indeed on the hotel's website, though. There are scammers out there who clone hotel websites...double check the URL and stuff.

Also always book your flights direct too.

Just don't use OTAs, ever, for anything. (ACTUAL travel agents are another matter, including purely digital travel agents and specialists like Equitours or cruise recommendation sites).