YABVU
I am only 20m older than my brother. It was fantastic. I loved having a sibling close enough in age to play with and my mum had no trouble giving us the time and energy we needed despite my dad leaving us when I was 7 and her trying to get a teaching degree over the next four years.
Children get emotional strength from strong attachments to, firstly their mother, and then other close family members - father, siblings, grandparents.
I have four children - 20m gap, 23m gap and 21m gap. They get so much from being so close in age. They are all happy and well-adjusted and make up the most fantastic games. They want for nothing, emotionally speaking.
My DH is 6 years older than his brother, and he wishes he were far closer in age to him.
Different age gaps suit different families and YABVU to make such judgements. You are completely discounting the benefits that children gain from having siblings close in age.
The only bad thing, IMO, about small age gaps, is the tiredness but it's worth it IMO.
What is damaging to children is when they are forced to be parented by an isolated, exhausted mother who's friends and family are not supporting her to do what she feels is best for her children.