There's certainly evidence that some people wanted other people to see them as obese - see
this sarcophagus from Etruria - but that's not necessarily the same thing. For example, a great deal of portraiture makes a conscious effort to show the subject as aged, weather-beaten or with imperfect features, but this may be more an ideological statement than a question of attractiveness. Oliver Cromwell's 'warts and all' portrait is the most famous example, but an awful lot of Roman portrait busts show their subjects with exaggeratedly craggy and wrinkly features, because Roman culture valued age and experience and distrusted the Greek ideal of smooth, almost boyish good looks. One might similarly imagine a modern boxer or rugby player showing off his battered nose, which - however much yours truly might wish it were so - is conventionally regarded as an ugly feature.
Your statement, then, is a dubious union of two suggestions - that being fat was a sign of affluence, and that it was considered attractive. I would suggest that the former is true, and that it led to obesity being shown off in the same way as a yacht or a sports car, but that the latter was probably not.
It should also be added that, except for 'mother goddess' figures, beautiful women in Classical art are always slightly slender by modern standards, although usually larger than modern fashion models and less curvy than those who grace the pages of gentlemen's literature. If you were likely to see
actually starving people on an average day's walk through town, you probably wouldn't go home and idealise near-starvation as an attractive body type.
The final caveat would be that 'the past' is rather big.