This is generally good advice, but I'm a grant writer (see http://www.seliger.com if you're curious) and have worked on many SBIRs and STTRs. I'll add that there are downsides as well. One is simple timing: if the appropriate SBIR or STTR funding cycle just concluded for that year, you may have to wait another year to apply. Then another 1 – 3 months for a decision. Then longer for final authorization of the budget. The other day I talked to a guy whose best potential SBIR source had had a deadline the month prior.
Second, Phase 1 grants can just be too small for the amount of effort that goes into them.
Third, they don't come with the advice / community / expertise of good VCs.
Fourth, they take a lot of effort to prepare, and for first-time grant writers they can be quite hard. The alternative is to hire someone like my firm. While I'm biased towards doing that for obvious reasons, we also cost money.
While I don't want to talk anyone out of applying, I do want to note that the downsides are considerable too.
As a side note, I used to submit some SBIR and STTR RFPs to Hacker News (search for "seliger" here: https://news.ycombinator.com/from?site=nsf.gov), but I stopped after a while because no one upvotes the submissions.