There's also the motivation factor (which might not be a concern for Oliver). Melbourne now have Oliver signed until 2030 and Petracca until 2029. Both are guns and probably top 5 in the AFL right now. But a lot can change over a couple of years and to have that much of the salary cap tied up in 2 players for so long is ballsy.
A deal like Oliver's is probably more likely to succeed than not but it can only take an ACL or something similar and suddenly you've got 6 years left of a contract at close to $1mil/year for a player who struggles to get on the park/is far from that value. See GWS with the Coniglio and Kelly deals.
Not saying it won't necessarily work out great for Melbourne but I disagree that the risk is low.
