This. Wikipedia has reached a point where most of what people are interested in writing about has been written about, or has been staked out by more active participants, leaving the bulk of remaining work either obscure or maintenance, neither of which is motivatingly interesting to most people.
Hence a recurring theme: the great failing of FOSS products (free as in beer) is precisely that a non-trivial amount of work which needs doing doesn't get done because there is no incentive to do it: it is hard, boring, unappreciated, and/or expensive to the point that the only way to get it done is to pay someone to do it. Unless Wikipedia pays somebody to round things out and constantly polish content, it will suffer stagnation.
Hence a recurring theme: the great failing of FOSS products (free as in beer) is precisely that a non-trivial amount of work which needs doing doesn't get done because there is no incentive to do it: it is hard, boring, unappreciated, and/or expensive to the point that the only way to get it done is to pay someone to do it. Unless Wikipedia pays somebody to round things out and constantly polish content, it will suffer stagnation.