I'm glad to support independent journalism while gaining ad-free access to quality content on a platform I frequent.
[1] https://www.nasdaq.com/articles/forecast-of-the-day%3A-twitt...
It's can be a Catch-22 in some cases. The same people most willing to pay to opt-out are the ones most coveted by advertisers.
Anecdotally someone I am close to doesn't seem to mind ads and regularly buys products from them, I block ads and rarely ever buy products from them. I'd pay for not being served ads in the first place
In the back of your head when you see the product the next time, you might think to yourself "I've seen this somewhere before... it's probably reputable." Or when you're in need of something, that brand's product might pop into your head sooner as something to assess.
On the other hand, I realize that services cost money to build and maintain, and if the subscription came with ad-free (and data-mining free! "ad-free - same great ad-tech data-mining flavor" doesn't count) I would definitely subscribe.
FB, for example, pulls 4-5x the ARPU for US users compared with international. I'd expect twitter to have a similar pattern (though it depends on what 'international' means: Europe is only half the US).
The other issue with this is that the most engaged twitter users are going be the likeliest to sign up for a paid twitter service. These are also going to be the people pulling the average up.