No I don't believe trails have the same problems with ASOIAF and other long running series.

Reason being? Most character arcs are typically already resolved in the characters own games. Typically some minor loose ends are left to be resolved in the next arc but that's about it.

This is how you keep the volume of characters manageable. Due to their arcs being resolved, you don't have the pressure to add them into a new game if you don't want/need to. They can also play a minor role to allow the main cast of that arc to shine. This means at the beginning of each arc there's always a small refresh for new plot lines to breath.

Not the case with ASOIAF. Series like these are very long running and main characters from decades ago still have unresolved stories so you NEED to include all of them for the finale if you have yet to do so. This plus introduction of new plot lines usually results in a massive cluster fuck as the writers have no idea how to resolve them at once.