No I'm thinking servicing is not considered at all, and for more reasons than just the typical managerial stupidity you cite. I'm thinking that they are costing themselves more in the long run when they have to pay for warrantee work that takes longer because of poor design. Penny wise pound foolish as the saying goes.
I can see a pre fab metal line being X length and pre bent with predetermined mounting points, causing an engineer to HAVE to mount it in such a way that it blocks access to PM work. I don't buy it though, SOMEWHERE in the design things have to be made to meet up without using generic pre fabricated parts. I think it's got more to do with thoughtlessness, and a lazy engineer; But I can see it happening.
In the specific case of a 95GT the metal line could have been shorter (less materials cost) and as a result would have been out of the way instead of blocking access to the plug. Or the bracket that holds it could have had a 30% bend, back or out, the line itself could have had another bend before the plug, or it could have mounted into the TB at a different angle. It could have been 2 inches further back or two inches further forward. Any of these would have worked. And there's no way in hell you could convince me that all of them were impossible because the engineers involved weren't allowed to do it; Or that they would all have cost more. More likely they simply didn't notice or care if they did.