The fact that only 10 people signed up was a shock to me. Of course, you can blame the version for everything, but if there was an option for mirror matches in the SoD, they would definitely be played there. And then, due to the lack of interest from the participants, the organizer also lost interest, which doesn't excuse him at all.

Playing a mirror match is pure mathematics. You don't get any enjoyment, constantly looking at where your opponent is and how many units I have now compared to him. But in Heroes, people play not only to win but also to enjoy the process, even if they lose. Where is the enjoyment if you are constantly worried about things like the date, the number of views, the number of castles, etc.? Moreover, in a mirror match, it immediately becomes clear how each player implements their strategy, and few people want this real comparison (without taking into account race, terrain, the presence of external factors, etc.), because they came to relax. When this constant comparison is happening in your mind, there is no room for excitement. What's the point of playing if it's the same in real life: you're counting at work, at school, solving everyday problems. You sit down to play Heroes in the evening or on weekends, and it's the same thing – where is the relaxation?:D
Therefore, mirror matches (and templates like Panic, Balance) are not very attractive in a PURELY GAMEPLAY sense FOR ENJOYMENT; it may be appropriate to use them in the later stages of tournaments.