I think there's a good case to be made for the digging element ("mole"): after Beagle, it was developed into a similar one which later flew on InSight. This newer one was not a success when deployed in 2019 - it failed to dig into the regolith. It seems plausible that had the team been able to deploy the Beagle mole - and probably find out it didn't work - that they'd have had a good chance to use that lesson to redesign the second generation.
In other words, Beagle probably wouldn't have got a useful result from that instrument, but it would have meant a later mission had a better shot at getting that data.
If the InSight mole had worked as planned, it would have given us more reliable data on Martian geophysics - how heat flows through the planet, which would have implications for determining its internal structure. There is a NASA summary of the objectives here.