I don’t know what straw man you’re destroying here, no one claims humans will go extinct without spaceflight. But without any doubt the loss of all space flight will have a major impact on how humanity organizes trade, communications, travel, agriculture, intelligence, war/peace, science.

And sure, ‘solutions’ will be found. Here’s another one for your list that will diminish the impact of the loss of weather satellites: just strap someone to a weather balloon and have them draw what they see, and drop those drawings until the person runs out of oxygen. Is it as powerful/convenient as what we have today? Hardly.