People nowadays bet more online than in physical objects - casinos, they are given the opportunity to bet in the comfort of their homes, without having to leave their homes and without the cost of transportation and accommodation.
or because it started with the increasingly difficult global COVID-19 situation, and more and more countries are advising or even banning their citizens from leaving their homes, and people are spending more and more time at home with their phones and internet now. And this is also the reason why the online gaming business is booming, because people have nowhere to go.
and whether the success of online gambling may affect casino or physical gambling.
There are a lot of reasons that people choose to play online and you've named most of the main ones. The sheer fact that internet connectivity and devices keep improving year after year enables more interesting casino experiences as well - every few years hardware gets cheaper and improves in processing power. Covid did instill a lot more work from home activity, which coincided with a massive uplift in online gambling site profits in those couple years, it makes you wonder how much people were really working? Financial tools are also improving rapidly, giving more people the ability to spend online with a variety of payment methods, which might have been restricting access to some people in the past.