Is value investing more or less frequent/pertinent - Now, 10, 20, 30 years ago?

Define "value investing". Buying stocks for than their net working capital doesn't exist anymore. Neither does most of the special sits style investing that Joel Greenblatt wrote about because he and his practitioners have picked up all of those free pennies. Buying equities at significant discounts to what a reasonable DCF / FCF based valuation would suggest and either making your return via share buybacks / cash return or waiting for multiples to mean revert is something pretty much every public equities investor with a holding period of longer than a week is doing / trying to do. Sometimes it works, sometimes you're right but you get your face torn off waiting for the market to recognize it (i.e. you're wrong). 

Regarding point 2- bull market or not it doesn’t matter. If you outperform in a flat or down market, your returns may still look crappy but you did better than everyone else did so you did a good job. Just have to be better than the average investor to outperform 

See the performance of the following "value" funds:

• Ranmore Global Equity Fund
• Artisan International Value

More generally, anyone on the Behind the Balance Sheet podcast is proof value is alive and well. 

True value is when you think a scenario you believe will occur is trading at a significant discount or premium. It's not simply screening low/high on multiples -- that might have worked in the old days as a proxy of value, but, like most signals, the alpha has significantly decayed. True value is extremely relevant.

1. Less common. Availability of data and news has made the short term more attractive in many regards. Yes, there will always be a place for people who can pick the right companies
2. Probably, but that's mainly because Buffett and Munger have the personalities for long term value investing. A lot of "value" investors I know give up too short. There are still plenty of good value investors doing well nowadays.
3. Availability of information makes finding mispricing harder. But I'd say main thing is temperament. You have to have a thesis and watch the market tear that thesis apart for potential years before things go well. Also, people have overly associated "value" with "cheap" which is not the case. Too many value investors either buy expensive but good stocks, or cheap but crappy stocks.
4. Activism is a whole other thing I'm not too familiar with, but I'd say probably only because getting a reasonable stake in a company to demand changes is harder and harder, but then again CEOs get sacked super often nowadays so who knows. 

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