Who knows Ryan Reynolds might not even get to play Deadpool in the future? Ryan Reynolds isn't confirmed to appear in the Mcu. They've said they would keep the tone of the Deadpool films and wouldn't make it pg13, but Iger/Feige never said anything about Reynolds moving to the MCu.
And sure Deadpool proved to be lucrative but any property can be successful if handled well, if not more successful than Deadpool. And this is Marvel Stud10s, not a struggling studio desperate for a franchise.
Personally speaking, like Ive said earlier, release Deadpool 3 in 2021 and let that be Reynolds' final Deadpool film. Then the rest associated to the Deadpool trilogy can be rebooted without the baggage from the Deadpool films eXisting in the MCU. Marvel Stud10s would be fine without a Deadpool film in the mcu for the 2020s. They have plenty of properties. They could reboot Deadpool in the late 2020s.