It depends on your Customer lifetime value (I'm assuming you're talking about paid media)
If you're marketing a toothbrush, then no, Linkedin is not the right place for you. You probably will take a long time to see return on your ad spend, if any at all.
If you're marketing products above $8k-10k, then yes Linkedin is a good place. These price ranges are usually enterprise products or services (B2B).
Many companies/individuals have seen success with Linkedin in terms of getting quality leads (decision-makers / professionals). Consider the mindset of Linkedin user vs a Facebook user. People go to Facebook to waste time and troll around. People on Linkedin want to get shit done, improve themselves, get a job and learn from others.
So the quality of conversations you get on Linkedin is higher.
Ask yourself these questions:
- Is my customer lifetime value above $8k?
- Am I targeting professionals?
- Do i have at least $5k / month ad budget? If you spend too low, you won't have any data to move the needle. Yes, Linkedin is expensive because the audience is premium.
FYI: The average Linkedin user has an annual income of 80k USD. These people are affluent and have cash to spare.