It is not obsolete insofar as it is a good source of Q/A material, which is useful to both humans (directly or indirectly) and bots. The only part of it that is obsolete is the search/query part. If the AI companies had an ounce of decency, they would see no problem injecting money into the platform to continue seeding that Q/A material which they have directly profited from. But investing in a commons is not on the playbook for vulture capitalism.