I don’t think it’s about personal injury, per se. Niantic released the game in a state where it had full access to some iOS users’ Google accounts. IMO this is more than enough justification for wanting to retain one’s right to a lawsuit in the event that Niantic fails to properly secure their software and/or user data.
These clauses are anti-consumer, without a doubt. Wealthy corporations like Valve don’t put them in their terms of service because they think it’s going to end up costing them more money. The threat of a class action is a powerful incentive for companies to take this stuff seriously, even if the resulting payout is trivial to any single member of the class.