As the original author of SUS, I see this sort of query a lot. I think you need to make a trade-off here, based on the fact that I first developed SUS 25 years ago when I was working on a usability engineering programme for the development of integrated office systems running on VAXes.
1) The terminology may not seem to be particularly relevant to any specific modern technology (websites, mobile phones, what-have-you) and people tend to attribute this simply to the sort of systems it was originally used to assess, and the fact that they differ from the sorts of systems and applications in use today. In some ways that doesn't matter anyway, because the individual items are not supposed to be meaningful in themselves. They are selected from an original, much larger pool of items, on the basis that they were the items that, when presented with extreme examples of usable and unusable systems, were the questions that led to the most extreme responses, both positive and negative. (Thus, in theory, examples of systems with less extreme usability characteristics, should lead to more intermediate responses). The sum total of all of these questions leads to a general measure of perceived usability. So you may disagree with the wording of individual items, but they aren't supposed to have diagnostic value in themselves or to relate to the specific features of a particular system that is intended to be used for a particular purpose. If you want that sort of information, you should write a questionnaire that addresses those specific features. However.....
2) SUS is 25 years old and because it was made freely available has been picked up and used in many, many usability evaluations. (Cheapskates! But I'm glad so many people have found it useful). Consequently there's a wealth of information out there about its use and a body of normative data. There have been some excellent studies done looking at its reliability and collecting normative data - in particular Tullis has an excellent paper on the former aspect and Bangor and Kortum have collected data on the use of the SUS over more than a decade.
So it seems to me you have a choice. You can devise your own questionnaire, which may use terminology relevant to the specific technology you're assessing. It won't have a mass of experience and data from other studies that you can compare it to. If all you're doing is comparing one version of a system or application based on a particular technology with a successor version, that may be all you need. But suppose you want to compare, say, a web-based application with one that's based around a different technology? Then you will start to run into the same sorts of problems that you perceive to be the case with SUS.
I've never claimed SUS to be a perfect tool. (I did say in the title of the published version that it was "quick and dirty"). But I think it's proved its worth over the years and the efforts of people like Thomas Tullis and Phil Kortum (who did all of their work quite independently of me) have provided additional evidence that it's a tool worht using.