No, I don’t think you should purchase a light blocking tent for growing mushrooms. You should get a translucent tent because it allows indirect light to come in.
There’s a common misconception that mushrooms should grow in a dark space. This is because of a relatively long history of growing mushrooms in dark areas, especially in France where farmers grow button and portable mushrooms in stone quarries.
The benefit of these quarries was not because they were dark, but because they held in humidity and maintained consistent temperatures throughout the year, allowing farmers to grow the mushrooms year-round.
Mycelium and mushroom fruiting bodies don’t need sunlight/UV light like plants, but they are guided by light for fruiting bodies to grow toward. I’ve read multiple studies on lights effect on mushrooms and mycelium, and the funny thing is that I can’t find definitive results for light versus dark, or even which color of lights is best.