It seems like advertising is backing away a bit, with the notable exception of the web. Ad-supported cable is dying but the no-ads premiums channels like HBO are doing well, and zero-ad subscription services like Netflix are cleaning up. The tech industry does seem to have more than it's share of advertising companies masquerading as something else. And the number of multi-billion dollar acquisitions for things like chat platforms, many that have subsequently been sold at a fraction of their purchase price, is suggestive of a bubble.
Ad supported cable is dying because a la carte is forcing what was once subscription based revenue (and thus concentrating on programming for a niche) is turning into ad-based revenue (and thus programming must attract eyeballs). So programming that could count on steady subscription revenue and concentrate on the topic at hand must now switch models and alter their presentation to go after what attracts eyeballs. This is a complete change and it's why ad supported cable channels added a bunch of "drama" and other things to formerly fact-based documentary programming. That drama (faked or scripted) attracts eyeballs. The more eyeballs, the higher the ad revenue.
Subscription based services like HBO and Netflix only care about growing subscription revenue, which means they don't care about eyeball quantity - they care about attracting subscribing eyeballs only. Their programming will be directed at what their subscribing public wants and what kind of subscribing public they want to get the dollars from.
So Netflix and HBO will be making programming aimed towards that demographic. You and I feel they're "winning" because we currently are in that demographic - the people who will likely see that programming and subscribe to the service.
But the market is still ripe for ads - the Superbowl for example, gets so many eyeballs its ratings are stratospheric. Which is why it costs over $100K per SECOND of ad time during it (that's $3M for an ad spot). For comparison, a prime-time 30 second ad spot generally commands $80-150K.
Sports, in general, are the highest rated programming on TV which is why they generally pre-empt other programming - the ad dollars spent is immense.