If 28 year old Isaiah Thomas doesn't match our "timeline", how does 31 year old Al Horford fit?
What do we do with him?
Horford's contract will be expiring shortly before our youngest players are due for contracts. If anything he fits the timeline perfectly to bridge the present and future. IT's situation is completely different and I don't see any parallels. Horford's basketball IQ, leadership, and consistency are all going to be valuable to this team for the next few years. We finally have a roster full of elite talent but it's very important to have some of the intangibles that a player like Horford brings.
We obviously have no idea how things will develop over the next few years but the worst case scenario is Horford plays out the next 3 seasons and leaves. Horford does nothing to prevent us from keeping the core of Kyrie, Hayward, Jaylen, Tatum, and Smart.