Good reporting and information summaries here. Modeling asteroid orbits for NEA/NEOs, main belt, and Centaurs for example is challenging. Main belt asteroids could orbit with a period near 4.4 years so in one billion years, could complete more than 227 million revolutions around the Sun. Now another new report indicates the early solar system protoplanetary disk likely had a gap in it based upon meteorite studies.
Scientists find evidence the early solar system harbored a gap between its inner and outer regions,
https://phys.org/news/2021-10-scientists-evidence-early-solar-harbored.html
Reference paper, Paleomagnetic evidence for a disk substructure in the early solar system,
https://www.science.org/doi/10.1126/sciadv.abj6928, 15-Oct-2021. My observation. The paper discusses the model developed, it is interesting and detailed. Different model rates of accretion are presented too showing different accretion rates in different parts of the postulated, solar system protoplanetary disk. Different areas in the early solar system accretion disk or protoplanetary disk could have accretion rates 1 x 10^-5 Msun yr^-1, 4 x 10^-9 Msun yr^-1 and 1 x 10^-7 Msun yr^-1. If a proto-Jupiter is used in the model, Jupiter could form in 10,000 years but this is not desired 😊 Using an accretion rate of 1 x 10^-5 Msun yr^-1, 3.33 earth mass per year could accrete in the early protoplanetary disk in our solar system. Using a minimum solar disk mass of 3300 earth masses, the early solar system accretion disk can disappear <= 1,000 years. So explaining the present population of asteroids documented today is no easy job, especially when considering protoplanetary disk models in use. Even the Moon forming giant impact scenario now seems to need at least two impacts to explain but this also opens the door to other challenging issues in the spinning, protoplanetary disk model used to show how our solar system evolved from a gas cloud. TWO IMPACTS, NOT JUST ONE, MAY HAVE FORMED THE MOON,
https://skyandtelescope.org/astronomy-news/two-impacts-not-just-one-may-have-formed-the-moon/
There is plenty of juggling going on in the models developed to explain how we evolved from a gas cloud today
