What I am talking about is not a minimally decorated church. There are plenty of parishes that started/start off as rather empty “shells” that are only greatly decorated in the sanctuary area, but which have a lot of architectural interest. I think of a Romanesque church, for example, where there are a lot of blank spaces which are anticipated in the future to be used for paintings, shrines, murals, etc. The building itself is in good taste, it’s just not completely decorated yet. As I understand, this is a very traditional way of doing things: build a completely sound and attractive structure, decorate well what needs to be decorated–like the sanctuary–and leave the rest to be decorated in the future by the parish over the years. I think this is an especially wonderful way for parishes that don’t have loads of money to build a church. I think there is an idea sometimes that “we have! to finish the church/hall/mall/school/store/whatever,” an attitude that’s more cultural than architectural in origin. I think to have a church that the parish can fill in over time is really cool and shows that the parish is alive.
I think what you have described is a pretty good way of doing things. However, if a parish ever feels pressure to accept a donation of an item, well, I think the better thing to do would be to just make a list of things the parish needs, reserve or pick out the specific objects, and just let parishioners memorialize them, like by inscribing the bottom of a chalice, or inserting a little pane of glass in a funded stained glass window, for example. Ie make a public policy of not accepting random material donations. To accept material donations can put people in very difficult situations. What if somebody buys a really expensive ceramic chalice? You definitely cannot use that at mass, but what are you supposed to do, say, “Sorry, we can’t use that?” Yikes! But anyway…
Rather, what I mean is the kind of interior that has no mouldings, no pillars, no things that hang from the ceiling, nothing at all that would add the slightest bit of architectural interest. And the churches that overwhelmingly fit this category are “modern” in design. Well, putatively…
And just to make it clear, no, I do not equate simplicity with modernity. The two are highly correlated–well, superficially anyway…–but there are vast troves of tasteful, simple old churches. The simplest little details can add major interest and warmth to a building. This is not about gilded flashiness at all (but that’s not bad).