From the original post, to my humble opinion, only 2 things are clear:
1 - Some data needs to be sent from the field device to a host computer.
2 - The distance from the devices to the host is approx. 100 meters.

Based upon these criteria, there may be a dozen or so solutions that will do the job nicely; one of those is RS485, I agree.

But ... one of the things this forum is intended for is to show that there are more ways to get there than the simple 'use 485' answer. My first posting was inteded to do just that. If anyone disagrees that my suggestion is a valid one: no problem! But it takes valid arguments to convince me of that. Simply stating that 'RS-485 is the best' doesn't come even close to that.

Of course can I think of additional arguments why 485 could be preferred over a current loop. But remember: the original posting did not mention anything with respect to state-of-the-art design, future compatibility, multi-dropping, easy connection to PC, and so forth. Similarly I could think of some reasons why 485 would in actual fact be non-preferred (for instance in Ex-harzardous applications).