Think all you want. You're wrong.
152 grams is 5.3 ounces. I get that off of a single plant with ease without even trying. Blurple lights CLAIM to cover that area, and as a veg light they're not bad. They actually can. But for flower power that area gets cut down.
But let's not take my word for it. Let's look at manufacturers data:
The Viaspectra 450 Par:
Veg area: 2.5 x 2.5 feet max at 32" height
Flower area: 2 x 2 feet max at 24" height.
Perfect Sun:
Veg area: 2.75 x 2.75 max at 30" height
Flower area: 2 x 2 max at 22" height
Neither one of those lights is really capable of getting a single plant to its max potential. You getting only 2 ounces per plant is a clear example of that. To wit:
Your 4 x 4 tent is 16 square feet. Both of your lights combined can only flower 8 square feet...or half the tent.
COMBINED.
The real drawback to them is their flowering potential. Autoflowers need a lot of light to really grow properly and from what you've said so far you're not only not leaving the lights on long enough, but neither light really has the flowering ability to give those plants what they really need.
But keep doing what you're doing if you're happy with it.