1. Vulnerable populations need more assistance accessing essential services required to participate in society
2. Service providers need to maintain a reasonable level of security for their customers
Can both be true. Saying that maximum (or minimum) levels of security are required at all time completely misses the point of security--which is to mitigate risk. How much risk is appropriate varies a lot by context.
Beyond the context of risk, there is reasonable debate to be had on how to best provide access to essential services to vulnerable populations. It's pretty important to have an email nowadays and if you're not tech savvy or an individual/community has little to no money to spend it's not unreasonable to have the reality of the matter be that there may simply not be many good alternatives (or awareness of alternatives) to GMail.
I'm not sure what a correct answer here looks like, but I don't think ignoring the need is an approach that gets us to a better society or enables vulnerable populations to better care for themselves.