A few months ago, the community decided to coordinate the activation of SegWit on August 1, rather than continue to delegate this coordination to the miners who all together and delayed this modernization. This proposal is called BIP148 and is widely supported by bitcoin users. There was a fear that 51% of the miners might not support consensus, in order to block the split into two independent chains of blocks.
Why BIP148 is no longer important
Last week, the miners finally decided to give up the failure of SegWit and started the activation process on their own - until August 1 (the designated activation day of BIP148), thus supporting BIP148 in advance. Therefore, the new rule BIP148 is redundant, since the miners already apply it as of Sunday. As for users, they must still run the BIP148 code to ensure that they maintain the security of the complete node. But the probability that the miners will try to split the block at this point in response is practically zero. In principle, BIP148 became an early unscheduled achievement.
Since August 1 - the launch of the new Altcoin "Bitcoin Cash"
In the meantime, a new altcoyin was created, called "Bitcoin Cash", which will attempt to capture users of bitcoin. Using the name "bitcoin", supporters of the new altcoyin can trick people into switching to Bitcoin Cash.
But Bitcoin Cash, after all, is just an altcoyin (or rather it will be called "Bitmain-coin"). It will not affect the real bitcoin network, and users who stick to Bitcoin Core and compatible software for complete nodes will not be affected.
Also note that this is not unique and not even the first such altcoyin, because Were "Bitcoin Dark" and "Bitcoin Plus", which also tried to capture the name "bitcoin". Bitmain-coin shows the same thing, even pointing to the launch date, August 1, although this "deal" has already been done earlier - with the help of the ALTkoins CLAM and Bitcore.
Nevertheless, there is one "greasy dirt" on Bitmain-coin - it will by default use the source code of bitcoin. This means that if you want to install or use Bitmain-coin yourself, it will ruin your bitcoin settings! But their "joint" use is the topic of a separate conversation.