>>> so we should convince them in some way modernisation is needed.
It is that, that is the real problem. The IT industry has a habit of promising a lot and failing to deliver. We know why, (customers don't know what they want, requirements added ad hoc, etc. etc.), but those that are the paying customer, (internal or external), will not accept that it is their fault. To a certain extent, they are right, they would not, within their own disciplines, tolerate the kind of cost/time overruns that routinely go with large IT projects.