I have worked every school day since lock down. Setting work for every timetable lesson, marking and commenting on the work produced. Responding to numerous e-mails from students. We have had video meetings for departments and year teams on a weekly basis just the same as we would have had in school. We have contacted parents about concerns over work or well being as we would have done in school. At this time of year we have curriculum reviews, schemes of work to modify, new guidance from Ofsted to fit in to our planning all of which is taking place as normal. Admittedly my pastoral contact with my form has been 4 days rather than 5 in the week.
I am absolutely looking forward to the opportunity to meet up with my year 10 and 12 students after half term, more important I believe for reassurance that they will be fine than for other purposes at this time. At that age the students understand the ideas of social distancing so unlike primary teachers I am not over worried on that score.
Anyway, the point is that teachers have continued to work throughout this period, unlike the lies that the Daily Mail have been spreading. The vast majority of students (I would estimate about 80% of my students have been working and have kept up with the curriculum.) It has been less stressful because there are no confrontations with those students that don't engage (an e mail is not the same as being there) but it has been work and pretty much full time work at that.
So No. Teachers should not lose their summer holidays. Students too, need breaks in the learning process (not as long as the archaic 6 weeks in summer in my opinion to be honest) but that is an issue for national policy for many years without ever reaching a conclusion.