In a sustained bear market, there's very little that has value in my opinion. As others said, signatures still work very well to spread the word, even if it's to less active users. I've noticed that the value of airdrops and bounties in general has declined due to the influx of new bounty hunter and airdrop participants. I think the tables will turn when there is not enough participants due to the lack of income, then the value of signatures will no doubt rise again. Given that a lot of the time the income is also dividable by no. of participants. To summarize: the value of signature campaigns is inverse to the price of BTC/crypto in my opinion, the lower the value of crypto goes, the higher the value of signatures due to a reduction in participants. However, the value of tokens will still be very low until a bull market returns.