Recently, there has been a genuine shortage of blood, platelets, and plasma ever since the COVID-19 pandemic. This has caused people to have to delay life-saving emergencies. This is a genuine shortage where people's lives are being affected by said shortage. Therefore, I believe it is a moral obligation to donate blood, platelets, and plasma as much as allowed by the donation center. By doing this, you are saving lives and it is pretty inexpensive and cost-effective.
Sources:
https://www.redcross.org/about-us/news-and-events/press-release/2024/red-cross-declares-emergency-blood-shortage-calls-for-donations-during-national-blood-donor-month.html
Furthermore, I talked to a person who took my blood. Can't provide a source on that, but I am guessing the person who took my blood wouldn't lie just like that.
"Does that mean there is no value in blood/platelet donation?" Of course not, I don't know why you would think that I hold that position. Do donate! I donate myself.
"Also, it is said that life-saving surgeries have been postponed due to lack of blood/platelets. I guess it is hard to say if the postponement results in death." I did not spot that in the source!
"Furthermore, I'm not entirely sure the shelf-life of blood/platelets is even long enough for there to be an importation from another country (ig it depends on the country)." The US is the biggest importer of blood, with roughly 20% of global imports going to the US. https://trendeconomy.com/data/commodity_h2/3002
Why do blood donation groups incentivize blood donation? I am not as familiar with the US; in Germany it is much cheaper to acquire blood by paying a donor $50 or giving them some food and drink than to buy it elsewhere. The Red Cross in Germany, to my knowledge, gives donors food and drink and then sells the blood to hospitals to make some money for their other charitable ventures.
Again, I do think it is good to donate blood! You should donate blood. I should donate blood. Others should donate blood.
I do not think it is probably the current most effective altruism.