A ruling endorsing Smith's free speech arguments, intentionally or not, could lead to widespread discrimination against the LGBTQ community and undermine the entire purpose of anti-discrimination laws. If the conservative "artists" are granted a license to discriminate, they would be free to propagate bigotry and even legally hang out signs in the future that refuse to serve Muslims, African Americans, or women.
Should Smith, who serves LGBTQ clients in other areas, be imprisoned for her refusal to work against her religious beliefs? Denying Colorado artists the right to choose their customers could affect the fabric of the US's free and diverse society. The First Amendment doesn't give the state the power to coerce its citizens to renounce their religious beliefs in favor of views they don't agree with.