Have you noticed the frequency of ads increasing on free services?

No. I haven't seen ads other than the occasional spam email that gets through the filter in years and I make every effort to avoid using a web browser (by using RSS, yt-dlp, wallabag, etc) to keep my personal attention economy a command economy.

Yes! Youtube ads have at least doubled in frequency and intrusiveness.

I returned to twitter after over a year, so I could see some links on a few email newsletters I get. Lots and lots more ads, mostly video, and mostly from what look like ChatGPT-generated company names: Dulale, Tuzely, Lucazoo, Lureza, Beitro, Keybla, Starcess. I see the exact same video posted by multiple "companies". How do I know? I make a habit of blocking all Twitter ads. If I see the same video, it's from a different "company".

No, I've declared a personal holy war on ads. I have many filters enabled on uBlock origin, and I don't own iOS devices on which blocking is less effective. If a website doesn't let me view with an Adblocker, I don't use it to the extent I can. I've had enough with ads and I think targeted ads should be wiped off the face of the earth. Answering the question, I see maybe an ad every 3 days.

I have noticed this as well. I speculate that it is knock-on effects from the tight monetary climate we are in.

I think there are a lot of companies that have an uncertain future and are trying to be "default alive". Perhaps the services they rely on have trimmed free tiers or raised prices?

Yes, the internet is becoming unusable.

Google search results are horrible and lead to low effort blogs by peacocking beginners who are trying to monetise a paragraph and 2 lines of code.

Paywalls and ads(if using without adblock) on anything interesting of value.

Social media is a information harvesting machine pretending to foster human connections.

Dating apps are designed to keep you single forever and owned by a single corpo.

News are owned by few folks as well and the only interesting discourse happens on X.

I have not, because I filter everything with uBlock Origin.