Their first hint should have been from the last time this happened in the 1980s and 1990s, and Hillsboro got built up from being a farm town in the middle of the last arable land west of Portland to one of the 5 largest cities in the state, now making it pretty much nonstop city from Forest Grove to Wood Village. Yet the gridlock is horrible because all the tax breaks that were given to build up the tech meant that there's nothing in terms of basic infrastructure to support it. Intel's campuses sit on two lane farm roads, with the exception of Hawthorne Farm (which has it's own MAX station), despite being, literally, in the middle of a city with more than 100,000 people and no mass transit to speak of (TriMet largely doesn't serve Washington County except for the MAX, and frequent service ends miles east of the economic incentive zone in Beaverton). God help you if your house catches fire or you have a heart attack at rush hour, nothing's getting through that traffic. But that's only the tip of the socioeconomic iceburg.
I was born and raised in Portland on Jessup and Garfield, just off of 99E, in the only part of town that has any racial diversity. I'm Cherokee, I'm bisexual, and I can't say I miss the low IT wages, unavailability of anything longer than a six month contract, employer abuse of H1B visas (we're looking at you, Intel, undermining a market with 20% U6 unemployment to basically hold wage slaves on the threat of deportation!), extremely high cost of living, and entrenched white-supremacist racism and homophobia. Or getting harassed by the Washington County Sheriff's Office, Hillsboro Police, Beaverton Police and the Portland Police Bureau on a twice-weekly basis for driving or waiting the bus while redskin (yet, good luck getting one of 'em to turn up any of the more than a dozen times my home was broken into or my vehicle stolen over the years; that only happened during a brief few months living in Salem, turns out Oregon State Police are the only professionals there). Or getting punched in the face by a total stranger for holding my boyfriend's hand on the MAX (Portland Police's answer? "Don't hold hands."). Worst yet, I didn't know this wasn't normal behavior for people until I just packed what I could into a duffelbag, spent the last of my money on a plane ticket, took the MAX one last time to Portland Airport and flew off into the sunrise, and discovered that Oregon, all of it, big cities included, is an unmitigated backwater yearning to be the hipster version of the Deep South.
You know your hometown has a problem when moving to an indian reservation in the midwest, sight unseen, a single bag of clothes, no savings, and no game plan, when the only thing you know that's waiting for you when you get there is a safe couch to surf, and even without taking advantage of any of the tribal benefits, it improves every aspect of your life personally and professionally, being the exact opposite of Oregon in every regard, with the sole exception of relatively minor things like sales tax rate (way lower prices and WAY higher wages more than offset this, though) and access to public transportation. I have my own car now (which hasn't been stolen yet, making 3 years and counting the longest I've ever owned a car), I have my own home now (which hasn't been broken into yet, equally record-setting), and I have job security and upward mobility (both of which are things you read about other people having if you're in Oregon).
Self sufficient income and personal safety are two things I deeply lacked in Oregon, and it's the three things I prize above everything else now (hey, you live the first 30 years of your life without those two things and the novelty won't wear off once you do). About the only way I'd ever go back there is if someone actually hired me with a high enough wage so that I don't have to deal with the locals unless I really want to, and make me well off enough inside a few months that I could go back home to Oklahoma and take the rest of the year off, or fatten out my retirement (retirement is something else that actually looks like it's not purely in fantasyland anymore). And I like Portland compared to some of the other folks I've seen show up living here that I knew back in Portland...
Oregon needs to wake up and start putting people back to work, because the longer Oregon slides deeper in to the Bush Depression of 2002, the more it reaps what it sows in crime, income inequality and poverty. You'd think they'd have figured it out by now given it's been getting worse almost half my life now. Oklahoma clearly figured it out.