What would happen if we would make so that coins with 131 years of inactivity would be reintroduced into the network?
The idea could be considered since mining and facilitating transactions is directly correlated with the current supply of bitcoin, so reintroducing lost crypto back to the market would spell good things for industry. Although it must be said that this only works if the supply is slowly increased, as flooding the market with lost bitcoins (if that's what you're going for) is a downright death wish. It will severely dilute bitcoin's value, and will cause multiple bank runs that could definitely end with bitcoin crashing.
Although in retrospect, with Satoshi Nakamoto gathering dust from elsewhere, who do we expect to do this for us?
I see no reason why you should be beating about the bush, because reintroducing lost Bitcoin into the network is one thing that is strictly impossible, as even Satoshi can not recover any coin that may have been lost. But another question we should be asking ourselves is "How can we identify lost Bitcoin?", because I'm sure there are many persons who still have access to their Bitcoin and yet haven't spent the slightest Satoshi of it. So such case, can you consider that as lost coin??