I'm not sure if I understand your question correctly - at least if I do then the data you've included are all not identical.
But if the question is "are all data in column 5 the same in ATF_1.csv and ATF_2.csv" then the answer is here.
atf_files = dir("ATF_*.csv");
isthesame = false(size(atf_files));
for ii = 2:length(atf_files)
atf_1 = readmatrix(atf_files(ii-1).name);
atf_2 = readmatrix(atf_files(ii).name);
if all(size(atf_1(:,5)) == size(atf_2(:,5)))
isthesame(ii) = all(atf_1(:,5) == atf_2(:,5));