By greatest invention I mean something that had big and positive influence.
We are in a time where a single invention can rarelt be great. For technological development you need thousands of small inventions, each that use previous technological breakthrough through decades of research. And even great things we have, are just refinement and miniaturization of things we already had.
But if a single thing had to be said, I would say mRNA vaccines. Covid vaccines saved milions of lives, were developed in record times, and their technology could be used for HIV or even antitumoral vaccines.
Was going to say that too. Regardless of the motives and driving forces behind the incredible speed at which the vaccines were developed (i.e. certainly a similar urgency could be applied to other diseases killing thousands and millions in poorer countries, but there ain’t as much interest in that), the mRNA technology proved quite powerful and an avenue to continue exploring in future research.
People forget that the research behind those vaccines had been going on for 30+ years. What was accelerated was the trials and the gathering and analysis of efficacy and safety data. The actual vaccine technology had been in existence for around a decade at the time.
The smartphone
Monero
I’m genuinely not sure that anything has been invented in the 21st century.
Many things that were conceptually conceived in the 20th century didn’t become viable until the 21st, such as OLED, VR and AR, raytracing, telesurgery, a whole slew of types of artificial organs, a gigantic amount of miscellaneous advancements in integrated circuit fabrication, alternative vehicle fuel such as methane, hydrogen and rechargeable batteries; maglev trains, innumerable safety improvements in aviation, mRNA vaccines and so on and so forth. I don’t think it’s fair to credit all that stuff to the 20th century, unless someone somewhere saying “be real cool if we could do that” counts as inventing something.
OLEDs were built in 1987 I saw my first VR demonstration in the 90s (and it wasn’t cutting edge then). I saw my first AR demonstration then as well as part of an undergraduate engineering fair. And so on. I just looked up maglev trains - in commercial use since 1984.
I don’t disagree that there hasn’t been refinements, improvements, or commercialization of technology, but there hasn’t been a technological leap or invention that I can think of in the 21st century.
To be fair, there’s only been 24 year’s of 21 century. Most things you gave listed happened at the end of the 20th century. But also the question is somewhat self negating - we won’t know what’s the greatest invention until we see it working great, but it takes much more than 24 years to take an invention from concept to consumption. For example computational biology is kicking off. Computer aided dna generation started in the past 24 years. But it’s so new few people think about it. Just like no one thought of internet as the greatest invention in the 70s… it was just too new
3D printers were a 21st century invention, I think.
Quadcopters and other multirotor designs resulted in an incredible leap in affordable cinematography, racing applications, rescue, mapping, and warfare.
