What versions are you referring to? Even LR5 is 64-bit.
The installer isn't, but the application is.
But yeah, older versions without 'native' support for proprietary raws, convert to DNG.
...then the Adobe DNG converter that will make a DNG from a Nikon Z9 NEF won't work either on Mojave....(OSX10.4; 24 september 2018 was its release)
(and probably LR10.5 will not read this DNG...)
All these inventions in software and hardware only cost money and make computers worthless after 5 years...
It is a bad thing: especially Apple re-invents the wheel every year ( to make things worse like connections, keyboards.... etc ... etc)
People who archive the digital Apple stuff and documents will get crazy....MS does a better job i am sure...
I look at my Aluminium macbook from 2008 to see how well it still works and how really litle has changed in design and usefulness.
i can even put new stuff in! like a battery.... Apple will re-invent that too - saving the planet as they want to... presenting it as new ... again...
Back to the future...!