Can you imagine both the 64-bit and the ARM transitions are the reason for this port to take such a long time? Imagine Feral started working on a 32-bit port back in 2017, then they first teased us with Bob on their radar in 2018, the next year they started working on a 64-bit port and at the moment they're working on an ARM port. No wonder Bob's been on their radar like forever. Let's hope they finish this port before Apple moves to AMD Ryzen CPUs.
The necessary work to patch at least some of the old games to 64-bit certainly didn't help any other projects, including "Bob". The switch to Arm won't have played a role until last week, as Feral couldn't have started working on that before they got their hands on at least one DTK.
Apparently there were some licensing issues with the music in the game that needed to be resolved.
So the delay has a mundane explanation. They may have just stopped working on it until those issues were sorted out.
As a side note, any game that uses metal has to be 64bit.