It's not terribly busy but for two things:
1) The town is getting through traffic, including trucks, going right through the middle. Not a great quality of life there.
2) Development on the north side will generate a lot more traffic, especially trucks.
So it's not a volume issue so much as a truck issue.
The construction of the Round Lake Bypass was indeed a requirement for the construction of a computer chip factory that is being constructed in nearby Malta. So while Round Lake itself may not have much traffic, expected growth in the near future, especially with truck traffic, has made the Round Lake Bypass necessary.
When I was still living in Albany, I had a conversation with someone working for New York State who had a hand in negotiating the deal that would bring in the chip fab plant. He said that with the construction of the chip fab plant and other technology plants, a sort of domino effect of growth would occur, since these plants would want their suppliers "right over the fence". These plants require a lot of gas and chemical suppliers, which need to be put right next door, etc. So, truck traffic in the area is expected to increase by quite a bit.
The construction of the Malta roundabouts on NY 67 is also a by-product of this factory.