Hm, well, nothing to do with Rohan Dennis, but the thing is not everyone has a smart trainer at home. There are lots of people confined to really, really tight spaces with people in their households they can't stand / don't get along with. I think cycling is not really important in this, but to not be able to go out, go jogging or walking, do some exercise, before you go nuts. I'm thinking about a lot of families, teenagers in precarious living conditions.
Yes I can perfectly imagine that lockdowns like in Spain can be incredibly tough for a lot of people both physically and mentally.
But Rohan Dennis is a pro athlete with well known mental issues riding for (at least what's supposed to be) one of the very best organised pro teams in the world, Team Ineos. I can't imagine Ineos not giving Dennis (and all their other riders) the very best support, both physically (smart trainers, training programs, ...) and mentally (sessions with mental coach, ...). DQS Team for example have already said that they work intensively with a mental coach who supports riders whenever they need to. I assume Ineos does the same, at least with riders like Dennis who already has a history of mental issues.
The fact that this still happened is in my opinion entirely on Dennis himself, unless there has been a complete lack of moral and mental support from Team Ineos which I can't imagine.