Requiring users to add their wallet addresses and not seeing a newly posted campaign ATM don't mean that the platform will be closed. For sure they require it for faster payment processing when the campaign ends. Also, I don't think it would be a problem because it's easy to add an address and you'll just do it once.
Quoted below the exact announcement made on their Telegram News channel.
Greetings, Dear Bountyhive Community
💈 Having an address before creating an entry has been mandatory for quite some time now. Thanks to this, leftovers are not necessary anymore! (and therefore will not be supported)
⭐️ If you didn’t enter your wallet for a campaign this year (Oracol, Stellar, EOS, etc), please make sure to do so before September 30th in order to be on the last batch!
Happy Bounty Hunting! 💰💰
EDIT: Added the TG Link on the quote