I have a 2012 MacBook running Catalina and an iPhone 12. MacBook requesting to connect never works. iPhone making the request works. But, the MB then disconnects after a several seconds or minutes. Some Bluetooth speakers can connect and be used by both with no problems. An Apple Watch connects to the iPhone but the MB does not see it.
So, there is nothing I can do to reliably connect the new iPhone to the old MB? The standards have changed too much?