I am under the impression that this is due to the dwindling number of students taking these subjects and /or the difficulty to find good teachers.
For reason number 1, the consequence is that different schools are trying to gather their students to diminish the cost to run the courses. For example, at my local grammar schools (which are single sex), from last September, girls and boys of the two schools are taught A level French and German together. For one language, It is cheaper to pay for two teachers than for four, as very often, two teachers are in charge of one A level course.
However, concerning languages, I have to say some places are still going strong!

I know a college where there are two classes of year 13 student
(and two classes of year12 students), some of whom are very strong linguists getting offers to study languages at Oxbridge and Exeter.
I wonder what the state of teaching languages will be in this country in ten years’ time….
Concerning computer science, I understand that it can be very difficult to find excellent teachers as many computing graduates find it more attractive to work for engineering groups rather than working in schools…