Depending on where you live, 2G may be the only option in some places due to much better range than all other generations. Also while driving for example, your phone may need to connect to a 2G base temporarily if there is a gap between the range of the 5G ones, so you may get calls dropping randomly
I would say there is. Many providers are disabling 3G nowadays and 5G is not available for all yet, so your phone essentially uses 2G and 4G. Now, imagine disabling 2G and calling someone on a moving vehicle...
No major U.S. carrier gas used 2G for years. Well, at least Verizon and AT&T. Sprint did as well before merging with T-Mobile. That are shutting down 2G this year. So, not really a big deal.