I come from a gaming background. I started writing guides and reviews so I wouldn't feel guilty about wasting my time - instead my gaming was "research" haha.
However I found that gaming wasn't the best area to write in, for the following reasons:
-Highly competitive. Both in individual articles and against big game review/guide sites.
-Articles get out of date quickly, especially if the games are online and get regular updates.
-Often games get old fast and stop being played, or in cases of online games, close down completely.
-Very low earning rates as people are there to read, not click adverts.
-Content isn't evergreen (as relevant in ten years as it is today.)