I was recently asked to bid on a project that involved some older technology and the potential customer kept the option open of a total rewrite. We logged into the website for a quick overview and I noticed that the site was written in (classic) ASP. Problem was (is) that the technology they have serves their needs and serves them well. Part of me wonders how many consultants prior to me had recommended a total rewrite just because the technology was one generation old.
I just can't do that with a good conscience. There is definitely a place for newest and latest, new development is one, increased interoperability is another. Simple changes to a proven, functional application is the best place to use works and works well. The one single exception to that would be the inability to find skills, experience or tools to support the older technology.
So, just as this potential client did, you should interview several people when considering a software developer. Chances are, if you are open and honest, you will eventually find a software developer who carries the same traits.