In reply to bimbling:
My personal view as to why the SNP MSPs voted it down:
It is not mainly because of the impending review of Permitted Development Rights. The review does, however, present another opportunity, although suggesting it is more appropriately dealt with there can been seen as kicking the can down the road.
It is rumoured that a number of SNP back benchers were sympathetic to Andy Wightman's proposed amendments to the Bill but the SNP exercises very strict party discipline and their backbenchers almost never step out of line. Whether you think this is a good thing or not is a separate matter. Those who wrote to SNP MSPs received very similar responses which reflects the central control being exercised on the matter.
The SNP considers that robust legal control of tracks have could have economic disadvantages. Any such disadvantages are negligible to the point of being irrelevant but the SNP's case for independence hinges on the economic arguments, so there is resistance to any changes which could conceivably be interpreted as having econmic impacts.
What would be particularly helpful would be if people, who are concerned that the current controls on tracks are inadequate and who are SNP members or are regularly in touch with SNP MSPs, ask SNP MSPs to press the case for change with the relevant Ministers.