It's interesting to note that mass advertising has gone through several stages, and a number of previously highly-active platforms are now pale shadows of their previous selves. Some of this is a matter of shifting technology and related advances, but there also seems to be a pattern of burning through audiences through frustration.

Arguably, advertising initiated in bulk print (newspapers and magazines), see Benjamin Day's The Sun (1833). I've mentioned Hamilton Holt's Commercialism and Journalism (1909) many times, it's an excellent summary of early advertising-based publishing, and its many problems: <https://archive.org/details/commercialismjou00holtuoft>.

Radio stole the thunder from print as a more passive and accessible medium, television from radio. Targeted cable offerings sniped over-the-air broadcast. And now online advertising is dominating both print and broadcast. I'd argue that billboard advertising has shown similar patterns as well, expanding rapidly with highway construction, seeing a strong backlash (beginning in the 1960s, notably by Lady Bird Johnson: <https://www.sandiegoreader.com/news/2001/jun/21/what-happene...>), and over the past several decades, trending strongly to very low-value advertisers ("gentlemen's clubs", lottery and casino ads, the classic anti-goods of alcohol and tobacco, as well as the increasingly ubiquitous "your message here" placeholders, being strong indicators of this, particularly outside high-wealth metro regions).

I don't recall who made the observation, but in the content industry, it's interesting that music, film, and books are exceptions to the advertising-supported nature (mostly, there are a few exceptions, mostly minor, though the expanding length of trailer and pre-film advertising in theatres would also be an exception ... this may have been mentioned in an Ezra Klein episode).

And speaking of Klein: that podcast includes advertising. I find myself averse to listening when I know I'm going to have to hear those (e.g., I can't intervene to skip the ads, such as when I'm doing household tasks), and will avoid listening to it. There are a number of other podcasts which are similar, a surprisingly large number being of what are nominally public-radio programmes --- Freakonomics comes to mind. Combined with IMO lackluster quality, I'm actively avoiding many of these, and have unsubscribed to several. Independent and academic podcasts are more my style, History of Philosophy by Peter Adamson and Complexity from the Santa Fe Institute being among the best.

And more recently, the vast expansion of direct marketing over p2p networks, most notably landline and mobile telephony, is making the experience of subscribing to those services increasingly undesirable. Much in the same way as spam and simply information overload seems to be making open-standards, universal-access email much less widely used (many organisations no longer publish email addresses, or respond to emails where such addresses can be found), an overall frustration level can in fact kill general use of a medium or channel.

John Gottman's five-to-one ratio of positive to negative experiences, originating in relationships but apparently having broader applications, may well play a role here. If even a relatively small minority of experiences over time with a technology, medium, or channel are negative, that impression tends to strongly discourage long-term favourability. See: <https://www.gottman.com/blog/the-magic-relationship-ratio-ac...> (for the relationship side, the ad/media extension is my own suggestion, though I suspect others have argued similarly).

As Nextgrid's comment notes, the real problem with advertising is that it's a race-to-the-bottom market, especially where high-value / highly-attractive audiences flee. Higher-quality advertisers similarly depart, and both the products marketed and methods utilised tend to ever-increasing toxicity in both figurative and literal senses. As I mentioned a couple of months ago, advertising ultimately has a reverse-Midas touch: it turns gold to shit: <https://news.ycombinator.com/item?id=32669503>

Part of the constant-platform-migration trend seems to be explained by highly-valued audiences tending to be early adopters of such platforms. Early advertising returns are high, and for all parties (publishers, advertisers, and audiences) the initial experience tends to be positive. With both wider adoption and early-adopter defections (leaving the media/platform), that kicks off the death-spiral dynamic.