Rubbish! I've taught in both primary and secondary schools and it is easier in primary for a variety of reasons, which is why after 5 years I decided to specialise in primary teaching. I agree every stage has challenges, but the life of a secondary English teacher is much harder than someone in primary with their own class.
Take, just one example, writing reports. You will have about 30 reports to write for your class as a primary teacher. A class you know very well and who you have taken across a whole year. Compare that to a secondary teacher in a school of (in my DD's case) of 1,688 of which she will teach about a third, ranging over all age groups from Y7 - Y13.
Or, in the primary class you are preparing your weekly English curriculum forecast and lessons for one age, for your 30 pupils, for one week. Now compare that with numerous classes, different ages, different curriculum areas, and so on.
Now let's look at the marking, or the behaviour, or ....no contest again.
I really admire our secondary colleagues.