To your first point, I don't think it removes several months I think that's an exaggeration, especially the 2025 part. He's pitching limited innings per start anyway. It might have cost him seven or eight additional innings. They would only keep him here if he was legit, and if he's legit and you're trying to win a world series, end of story. He stays and helps you try to win. That takes precedence. You can continue to work his arm up in the off-season and carry forward with whatever plan you want. It wouldn't have been detrimental. The experience is also more valuable than facing minor leagues schmoes in minor league parks.
To your second point, I don't care about sending down some schmuck for a stud. Also don't care about paying him sooner if he helps you win. Championships are the point. It's the only thing that matters. A chance to add a stud pitcher to your team needs to be done if it's available.