While the capabilities of Pegasus may vary over time due to software updates, Pegasus is generally capable of reading text messages, call snooping, collecting passwords, location tracking, accessing the target device’s microphone and camera, and harvesting information from apps.
Once installed, Pegasus has been reported to be able to run arbitrary code, extract contacts, call logs, messages, photos, web browsing history, settings, as well as gather information from apps including but not limited to communications apps iMessage, Gmail, Viber, Facebook, WhatsApp, Telegram, and Skype.
https://en.wikipedia.org/wiki/Pegasus_(spyware)
“Once installed” is operative here. Pegasus isnt a magic wand that you can swish to read all text messages on every phone. It needs to be deployed.
indeed, unless you’re a target for a state or a company that cares to spend money to spy on you, you don’t need to worry about pegasus