Disappearing web services due to changes at X, aka Twitter

One of the changes at X, formerly Twitter, that I disagree with has to do with curtailing access to its application programming interface. The previous openness of Twitter’s API created an ecosystem of useful services.
New owner Elon Musk cut off free access to Twitter’s API and initiated a pay-to-play plan as a means to raise revenue for the service. But the move negatively impacted researchers, government entities and small businesses that didn’t have the resources to pay for access.
One of the services I liked that stopped working because of the Twitter API changes was iUnfollow. I used iUnfollow for my work Twitter account to quickly and easily unfollow Twitter followers who did not follow me back. For that account, I use a reciprocal approach to following people.
IUnfollow says over 320,000 accounts used its service to perform more than 100 million unfollows since 2011. But the service stopped working for me and others in March 2023.
Similar websites that provided Twitter-related services also have gone dark including Tweepi, Twopcharts and SparkToro.

Photos: Screenshots from iUnfollow, Tweepi, Twopcharts and SparkToro.