Therefore, it's possible that a tiny 13-inch MacBook Air M1 is more powerful than the most cutting edge of MacBooks released in 2019 and 2018, correct? Or am I missing something here?
First, that comparison is soon going to be irrelevant: those i9 Macs are being replaced by M1 Pro and Max machines - and while that shouldn't change the single-core benchmarks much compared with the M1, it will really show up in the multicore scores. Going forward, M1 (and the M2 in the future) are going to be the "entry level" for Macs.
Second, it's not all about raw CPU power as expressed by Geekbench. The Intel i9 MBPs support more RAM and more Thunderbolt/USB3.1 I/O bandwidth. The M1 GPU blows the Intel
integrated GPU in the old Airs and 13" MacBooks - and is particularly good on applications that are optimised for Metal and particular video codecs, but it is only really equivalent to a so-so
discrete GPU and the GPUs in the higher-end Intel MacBook Pros will probably beat it in general - except on those well-optimised apps. The M1 Pro/Max machines offer better GPUs, more I/O and more RAM than the plain M1.
So it really comes down to what your workload is, whether it is limited by RAM or I/O bandwidth, how much advantage it gets from multithreading, whether your software benefits from specific hardware acceleration in the M1: some applications will run like the wind on the M1, and the new MB Air can certainly play in a different league to the old one. Others may be better on Intel, especially the higher-end 16" MBPs.... and the new M1 Pro/Max will beat the Air hands down on jobs that use multiple cores, are GPU heavy or which benefit from more than 16GB RAM.
Basically, the M1 blows away anything based on ultra-low-power Intel chips with integrated graphics ('ultrabooks' and ultra-small-form-factor systems), the M1 Pro/Max MBPs blow away any truly mobile laptop (their real competition comes from significantly heavier, power-hungry 'mobile workstations' and 'gaming laptops' - a market that Apple doesn't really address) while Apple have yet to show their cards in the mid/high-end desktop category - which is going to be a harder sell for them, because Apple Silicon's strengths of low-power/low heat/long battery life are less vital there - so it depends on how much Apple is prepared to invest in developing workstation-class processor/GPU combos.