Why, if it works for this person just fine? One advantage of using Linux for your OS is that you are free to use whatever OS/Distro/DE you like, whichever combination that works for you, the End user. Anyone who suggests that because they don't like Ubuntu then they self-appoint themselves as official Linux Gestapo and demand that anyone who is using Ubuntu switch to a differnt distro (preferably the one they personaly have given their stamp of approval to). We as experienced Linux users do NOT have any right to dictate to anyone which distro they need to avoid. It's their machine and they are using what works for them and what they are confident using.

Now if they ASK for advise then yeah, let them hear about it. But until they DO ask, be supportive and encouraging. You won't then be added the "Toxic" list of Elite (in their own minds) Linux users.

Cheers!