This is going to be an argument about the common, let's say, clientele on this subreddit. This means I'm going to try to show how obesity is not so prevalent among the people that guys and girls on this subreddit want to date, not the general population. In the latter regard, it is a huge problem indeed, but it's simply distorting reality when the argument "The average person is obese" is made here, and literally all adults BMIs are used in the average, yet probably like 1% at most are dateable for an individual.

So!

Higher parental education "reduces" obesity:

Among children and adolescents aged 2-19 years, the prevalence of obesity decreased as the head of household’s level of education increased.

(This is a code word for "higher class")

Furthermore:

Obesity prevalence decreased by level of education. Adults without a high school degree or equivalent had the highest self-reported obesity (38.8%), followed by adults with some college (34.1%) or high school graduates (34.0%), and then by college graduates (25.0%).

So if we are talking about college-educated people, obesity is already much less prevalent.

Severe obesity:

During the same time, the prevalence of severe obesity increased from 4.7% to 9.2%.

It makes sense to exclude severely obese individuals, yet a 500 lbs person will increase the average disproportionately to their relevance in real life.

Young people:

Young adults were half as likely to have obesity as middle-aged adults. Adults aged 18-24 years had the lowest self-reported obesity (19.5%) compared to adults aged 45-54 years who had the highest prevalence (38.1%).

Since even 35 is considered old here and settling-age, it is just dishonest to mix those groups while one is twice as obese.

Disparity by race:

Non-Hispanic Black adults had the highest prevalence of self-reported obesity (40.7%), followed by Hispanic adults (35.2%), non-Hispanic White adults (30.3%), and non-Hispanic Asian adults (11.6%).

Perhaps not relevant, but if you have a preference, it could be a huge difference in how obese your preference is.

Depending on your age, education and socioeconomic class, the argument "the average person [that you want to date] is obese" can quickly become very wrong. Although this isn't necessarily the case to the same degree everywhere. All of those factors above also add up, so younger and college-educated and Asian people will be much, much lower than the national average. And maybe exactly that is your type.

A little fun statistic:

Non-Hispanic Black adults (49.9%) had the highest age-adjusted prevalence of obesity, followed by Hispanic adults (45.6%), non-Hispanic White adults (41.4%) and non-Hispanic Asian adults (16.1%).