Putting the store of value argument and participation/governance rewards (~17% right now from reserves) aside and just focusing on the network utility we can calculate the investment return using the following parameters and a basic simplified model:
N: number of transactions per second
F: transaction fee
P: profit margin (net profit percentage to the network revenue after deducting costs like running relay/archival nodes)
Another aspect of valuation is how co-chains and sovereign chains impact the scarcity story. The fees on those chains are paid using their own coins not $Algo. The main question is what ensures that the Algorand network (supervised by the foundation) remained the main blockchain in the algorand ecosystem and hence can preserve and grow its value.
See comments under this post: https://www.reddit.com/r/AlgorandOfficial/comments/qpk5sq/is_this_the_first_confirmed_co_chain/hjv1nld/?context=3