Without going the full Mick, it's an interesting question. Fyfe is 29 this year, so maybe two years left before the decline really kicks in. If we're not a better team without him now, we've got two years to bring through the next generation so that we will be.
Sadly, I recall this type of conversation about Pav, and we've never recovered our consistent forward scoring potential after Pav started to fade late in his career. I put it down to not managing to draft or develop a strong forward coming through the ranks. It would be good to avoid a repeat of this and have someone ready to step into Fyfes shoes.
The larger question would be whether the team down at Cockburn HQ think that we'll win a premiership in the next 2-4 years, if not, may as well blood the young ones at a faster rate than we're doing at the moment.