If something called the service industry did not exist, I could be happy.
I would be happy if there was no such thing as a service industry.
I could become happy if the service industry did not exist.
サービス業 = service industry
というもの = something called...; such as
無ければ = if there was no/not...; if...did not exist
幸せ = happy; happiness
なれる = can become
「なれる」は、can become という意味がありますが、英語では would be happy の方が自然でよく使います。「というもの」は、something called と訳す人もいるかもしれませんが、私の意見では、この場合、such thing as の方が元の日本語の意味とニュアンスに近いと思います。
そして、将来のことなのに、would や could (過去形)を使います。
なぜなら、仮言的な表現ですから。
✖︎「I am happy if there is no such thing as a service industry.」は、少し不自然でおかしいです。
○「I would be happy if there was no such thing as a service industry.」がいいと思います。