Today, the World Health Organization has a tobacco FAQ evading the question of whether vaping is more or less safe than smoking tobacco:

Are e-cigarettes more or less dangerous than conventional tobacco cigarettes?

Both tobacco products and ENDS pose risks to health. The safest approach is not to use either.

The levels of risk associated with using ENDS or tobacco products are likely to depend on a range of factors, some relating to the products used and some to the individual user. Factors include product type and characteristics, how the products are used, including frequency of use, how the products are manufactured, who is using the product, user behaviour – user’s puffing style – and whether product characteristics are manipulated post-sale.

Toxicity is not the only factor in considering risk to an individual or a population from exposure to ENDS emissions. These factors may include the potential for abusing or manipulating the product, use by children and adolescents who otherwise would not have used cigarettes, simultaneous use with other tobacco products (dual or poly use) and children and adolescents going on to use smoked products following experimentation with ENDS. Dual use, which is common, is at least as dangerous and likely more dangerous than smoking conventional cigarettes or using e-cigarettes alone. Further, not all ENDS are the same and the risks to health may differ from one product to another, and from user to user.

For comparison, the British NHS states:

Nicotine vaping is less harmful than smoking. It's also one of the most effective tools for quitting smoking.

How will the WHO answer this question on January 1, 2050?

They don't need to answer it in exactly the same format as today's FAQ - a brochure or TikTok would count, as long as it's clearly the official position of the WHO. If they respond to the question in multiple places, it will resolve based on the place that a typical American adult would consider to be the most prominent.

If the WHO no longer exists but there is a single clear successor organization, this question will resolve based on the position of that organization. If there is no clear successor it will resolve "The WHO will not exist in 2050".