My direct experience of the Axel is very different.
Over the years, I've stayed there many times with different boyfriends. And when I was single and stayed there, I had different companions (working and non-working guys) visit for a session and some stayed for breakfast. In fact, as a regular frequent visitor to Barcelona, I found that other smart hotels were just as "gay friendly" as the Axel.
As in any hotel, as long as you the guest and your visitors are respectful, not obviously high nor falling down drunk, there will not be difficulties in Spain. Security concerns may mean that Reception wants to know of any visitors to your room and may check their ID but since the hotel is concerned for my security, I have no problem alerting them to the expected arrival of Jose/Ignacio/Lucas et al.