SEO makes it harder for people to find useful information on the web instead of what someone spent time and money to "optimize" for Google. Developers know this, and so generally dislike SEO.
SEO allows small/smart companies to compete against established behemoths in search engine results.
Your statement is true of ALL marketing and ALL sales. The truth is that marketing and sales efforts are a success multiplier to the quality of your product. Yes, that means that good companies can get beaten by crappy companies who out-execute them in the arena of sales and marketing.
You can ignore sales and marketing in the hopes that your product is SO much better than the competition that it will win anyway... But that's almost never the case (note the $ that Apple spends on marketing, bizdev, and branding).
Many developers are developers precisely because they didn't want to get into these zero-sum games. Think of the other professions where smart, logical, creative people can end up. Finance, law, and advertising. Most of these pay better than software engineering does. If we wanted to go into them, we would've. But it's precisely the constructive, innovative part of software development that appeals to us.
The question was "Why do developers not want to go into SEO?", not "Why do salespeople and marketers not want to get into SEO?" It's because the question is already self-selecting for the people that don't want to do that. If we liked gaming the system for personal gain, we'd work for Goldman Sachs.
If you leave low-hanging opportunity on the table because your software business won't lower itself to things like sales, marketing, SEO, PR, etc-- you're doing a disservice to your investors and your co-founders.
My biggest gripe as a developer is having to deal with the perceptions of non-technical folks. I still frequently encounter folks who hope SEO can magically redeem their lousy-to-mediocre website. I always encourage them to first build content worth finding before going nuts worrying about how many people will find it.
This is sort of like saying "good programming is mostly easy, common-sense techniques that don't change very often", and since programming is a solved problem, anybody willing to pay a lot of money for programmers is clearly getting something hinky done.
Programming is not a solved problem. Neither is marketing. SEO exists at the intersection of programming and marketing. Every site and every business brings their own unique challenges to the mix, and they're not all addressable with "Slap some alt tags on those images and you're good to go", any more than you can solve any programming problem with "Rewrite it... with more AJAX!"
SEO for many startups will involve, among other considerations, "How do we convince our users to create? How do we convince our users to share?" Those are core product/marketing questions for many startups, but they're equally core to the SEO strategy, and they're tricky to get right. For that sort of startup, you could imagine someone looking over their widget's viral activity with the amount of intensity that Zynga spends on its viral channels, because sharing via the widget creates several types of value for the company (via direct traffic, branding, and ranking effects).
I think the main issue is that most developers/business owners have seen SEO companies charge enormous sums for adding very little value, or using dubious ethical means such as link farming, keyword stuffing, invisible keywords and so on. It's going to take a long time for all of that to wear off.
A lot of the time, especially with small common issues, the answer is standard and simple and you could have just looked it up yourself. A lot of sites actually just need to pick some decent keywords to target and write titles for the page.
Sometimes, you want a professional to tell you that even though it is mostly just standard stuff because otherwise you don't know if you could be saving tax by doing something else.
Sometimes things are complicated and the difference between a creative (which usually also mean experienced) consultant helps.
BTW, that doesn't mean rely on professionals and don't learn it yourself. Learning a bit of law or accounting might also be a good idea. Certain types of creative solutions are only really going to come from you. Some solutions are best engineered in from the beginning. EG, you might want a lawyer on the founding team of a music sharing startup.
Bad SEO is easy, good SEO is hard. Just like anything else in life; nothing worth having comes easy.
He wrote "good SEO" meaning ethical or non-sleazy and "bad SEO (gaming the system)" as sleazy SEO.
Not your re-defining them as "good" as "effective" and "bad" as "incompetent".
Thankfully, I haven't worked at a company that hired a "bad" SEO firm, yet.