I've seen similar thoughts expressed here and on Facebook. There are multiple problems with the logic of the argument that you're just delaying the inevitable. Delaying the inevitable is an excellent strategy in reducing overall deaths from the virus for several reasons:
1. It spreads cases out so that hospital beds, particularly ICUs, and medical equipment/personnel don't get overwhelmed. Herd immunity takes about 70% of the populace getting infected, so that's about 230 million people in the United States alone. A small percentage require hospitalization, I haven't been able to find an exact figure, but even 1% would equate to 2.3 million people needing to be hospitalized. Spreading that out over months instead of weeks means a lot fewer people die.
2. It allows time to develop vaccines, antibody treatments, etc. to reduce the number of people who die from infections. If an effective vaccine can be found, herd immunity can be achieved through that rather than having people get sick.
3. While most people get well, beyond those who die, the disease is proving to have long term impacts on health for a small percentage of the population. Some of these impacts may ruin lives for good.
4. We don't know if/how long recovery from an infection gives you immunity. In a worst case scenario, there may be no such thing as herd immunity for COVID-19 if there isn't a fairly long-term immunity.