Not only have I carried concealed for 34+ years, worked in gun shops, shot competative IPSC/IDPA and teach defensive firearms classes to newbies the best carry gun is an unanswerable question. Recently had a female student who was a long distance runner and of very slight build. She wanted to carry a gun but on 10 to 25 mile training runs was not going to carry anything heavy. I always try to expose my students to at least a dozen firearms before they purchase their carry gun. My smallest and lightest 380's she liked the weight but had issues with ergonomics of a semi auto. Also recoil was an issue with her size. She is carrying a "Scandium" S&W 351 PD in 22 Mag. At 10 ounces unloaded and we'll under a pound loaded with Hornady Critical Defense FTX. In this case the gun carried beats the gun left at home or in car.
I generally carry a SIG 2022 in 40 Smith with tritium sights as my work gun due to harsh environment. Whenever not working carry a 1911 Government Model. Usually have a 5" full size or even a 6" long slide as my primary and a SIG 1911 Double Nickle Compact as a backup since use same ammo and magazines. Other days will still carry a 5 shot 3" barrel 44 Special with two speed loaders. On even rarer days might catch me with a 9mm Hi Power or SIG but am very selective in 9mm ammo choices as feel it's a minimum caliber and why for competative use falls in minor cartridge division. Sometimes when have to be ultra discreet carry an AMT 380 Backup of which own seven as wife loves them for size and we stash them everwhere, especially when riding motorcycles. Mine are 100% reliabe as all carry guns get 500 rounds fired before trusted with my life. Any glitches are addressed with good gun smithing.
My wife who has a degenerative bone disease carries a Walther PK380 with Hornady Critical Defense as a primary most times but in her truck there is a 5.7×28 AR 15 in police style lock under back seat. She has three of the Walthers, all well shot and two required some smith work for 100% reliability and a pair of Colt Diamondbacks she confiscated when discovered how slick they shoot loaded with the low recoil Hornady Critical Defense with pink tips. It's offered in 380, 38 and 9mm with all still in her ability to shoot. She keeps a SIG 9mm with the low recoil Critical Defense and an Osprey suppressor on night stand.
Have clients that often choose a compact carry in 380 or 9mm and duty size 9mm or 40 Smith for home defense. So here is the conundrum... Asking which gun is best for CCW is like asking someone what is their favorite Sunday evening meal or favorite movie. I can run a dozen couples through a private class and have the twelve women choose one or two weapons totalling 16 models and men do the same. Try to get them trained on best concealed carry for each and a single duty size for home defense they share. Doesn't always work out like that. My 77 year old mother carries a S&W M-60 in 38 Special and after 40 years can shoot your left eye out from any distance someone is a threat.
Thus I suggest a class or finding a collector or group where can try a myriad of choices. Ranges that rent a wide variety of handguns is another answer. Not only should a handgun be comfortable to carry but comfortable to shoot. It needs to fit a person's individual needs and they need to practice with it regularly and take a class if new to carry. I mention Hornady Critical Defense ammunition often as its good stuff, reliable expansion and available in have hitting Critical Duty, slightly lighter Critical Defense and the pink tipped low recoil flavor. All tests well for me. If want a more budget friendly ammunition the Federal HST is also a go-to choice for me and recommend often. So not only is the question what is best handgun but also best ammunition and best holster or method of carry. I have several dozen holsters, not all can invest over $1,000 in leather choices.
Also there are special circumstances that might dictate your carry handgun. Like the lady long distance runner being tasked with the 10 ounce 22 Magnum a person fly fishing in Alaska might need a 454 Casull Magnum or 500 Smith. Someone mentioned a while back in this thread having issues with 380 acp pocket pistols. Have seen many that were goofy and many that were perfect. Why it's suggested a few hundred rounds minimum be fired through any carry gun purchased to learn it's nuances and all aspects of your personal situation considered. While I find a 380 marginal, with modern ammunition it beats no gun but only if it functions and hits what aim at. Have seen many men come in gun sfores, buy a 1911 in 45 and bring back to trade in due to issues with recoil in under two weeks.
Why all new gun owners should test drive, not just hold in a gun shop any handgun they might consider purchasing unless can afford to keep buying till get it right in the interest of building a collection. Then your tasked with finding amunitions it likes, not all guns like all ammo plus correct holster. How is that for narrowing down your choice. Why my students handle a minimum of a dozen handguns and sometimes upwards of twenty different choices before settle on what they feel comfortable using, carrying and defending your life.