>If everybody used a DNS blocker to filter out ads, would online advertising exist as a business?
Absolutely. Companies would get more clever about cloaking advertising with inscrutable domain names that's hard to filter with regex. Youtube is a good example of ads that are hard to block using pure DNS. (But that doesn't stop people from trying new variations of regexes for pihole that youtube eventually breaks.[0])
The other technique is native advertising. (But native ads are actually more "relevant" so somewhat more tolerable and more people would actually pay attention to them.) E.g. I just saw a Linus Tech Tips (the computer tech channel) and the pre-roll ad is for D-CON mouse traps (not relevant to me since I don't have a mouse infestation that requires rodent traps) or girls dolls[1] -- but the native ad is Linus acting as spokesperson for the Ring Doorbell Camera Kit[2]. That's more relevant since it's a techie gadget. I won't buy the Ring kit but it's more relevant than the mouse trap ad.
Absolutely. Companies would get more clever about cloaking advertising with inscrutable domain names that's hard to filter with regex. Youtube is a good example of ads that are hard to block using pure DNS. (But that doesn't stop people from trying new variations of regexes for pihole that youtube eventually breaks.[0])
The other technique is native advertising. (But native ads are actually more "relevant" so somewhat more tolerable and more people would actually pay attention to them.) E.g. I just saw a Linus Tech Tips (the computer tech channel) and the pre-roll ad is for D-CON mouse traps (not relevant to me since I don't have a mouse infestation that requires rodent traps) or girls dolls[1] -- but the native ad is Linus acting as spokesperson for the Ring Doorbell Camera Kit[2]. That's more relevant since it's a techie gadget. I won't buy the Ring kit but it's more relevant than the mouse trap ad.
[0] last time I tried many of these DNS regex ideas, youtube stopped working: https://www.google.com/search?q=pihole+regex+block+youtube+a...
[1] ads for girls dolls probably ignored by 99% of audience demographic of Linus' video: https://imgur.com/a/gPcxOJ3
[2] https://youtu.be/hiLlNzxDfAg?t=19m12s