system
Given the following post, respond as if you're commenting on Reddit:
human
The Human Genome Project cost $2.7 billion. 20 years later, it costs <$1000 to sequence the genome. Was the cost of the project fundamentally necessary for subsequent progress, or could we have "waited" for the technology to become cheaper?

I'm very much a clueless layman, but I'm learning about genetics for the first time. I don't mean this in any sort of combative way–the Human Genome Project had countless benefits that we can't possibly track, and I'd imagine $2.7 billion is a trifle compared to its broader impact. 

My question is just narrowly about the way that genome sequencing has dropped rapidly in cost. Was it fundamentally necessary to first use these exorbitantly pricey methods, which provided the foundation for the future research which would make it affordable? Or are the two questions inherently separate: the Human Genome Project gave us a first, initial glimpse at our mapped out genome, and then a decade later separate technological developments would make that same task much cheaper (as is commonly the case in science and technology).

The "could we have waited" in the title is probably misleading–I really don't mean any sort of  value judgment (the project sounds enormously important), I purely mean "could" in a narrow hypothetical (not, "would it have been a good idea to wait", which I highly doubt).
gpt
The cost of gene sequencing has dropped dramatically, but these two numbers are apples and oranges. The Human Genome Project "mapped the genome". Meaning it created a "reference genome" that is roughly accurate for every human being on earth. It's like a scaffold upon which you can place any individual sequence you might read. 

Today, you can take short reads of roughly a human genome-worth of DNA for less than $1000. That sequencing can tell you if the person has any small mutations. But without the reference genome, all that information would be worthless because you couldn't place all the little fragments of DNA where they sit on the larger genome.

Think of it like having a big jumble of small phrases that you know belong in a big epic novel. Your job is to tell us what page the phrase belongs on. HGP pieced together the whole novel for the first time, so now your job is much easier because you can just do a CRTL+F. 

Today, people continue to assemble new reference genomes (e.g., new species) and reassemble the human genome to look for larger variations that don't agree with the original reference genomes created by the HGP and others. You typically can't do that for <$1000. It could cost you tens or hundreds of thousands of dollars, depending on what tools you use and what accuracy you desire. 

Tl;Dr: creating a new reference genome is much cheaper than it used to be and has certainly enabled by technology created in the course of the HGP and others. But still very very expensive.