It looks like I have a problem with my otbconf.profile. I do:
alobo@Delia:~/OTB-6.6.1-Linux64$ echo $PATH
/home/alobo/seadas-7.5.1/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
alobo@Delia:~/OTB-6.6.1-Linux64$ ./otbenv.profile
alobo@Delia:~/OTB-6.6.1-Linux64$ echo $PATH
/home/alobo/seadas-7.5.1/bin:/usr/local/bin:/usr/bin:/bin:/usr/local/games:/usr/games
alobo@Delia:~/OTB-6.6.1-Linux64$ otbcli
bash: otbcli: command not found
Instead:
alobo@Delia:~/OTB-6.6.1-Linux64$ export PATH=/home/alobo/OTB-6.6.1-Linux64/bin:$PATH
alobo@Delia:~/OTB-6.6.1-Linux64$ otbcli
Usage: /home/alobo/OTB-6.6.1-Linux64/bin/otbApplicationLauncherCommandLine module_name [MODULEPATH] [arguments]
My otbenv.profile here: