Is the doctrine nowadays that it is very important to receive the Eucharist if you as a Catholic attend or hear Mass?

I've noticed that nowadays most people who attend Mass receive the Eucharist. It seems like all who are Catholic receive it. I have read that it was way different in the past. People could attend Mass on Sundays and not receive the Eucharist, if I'm correct. Mass obligation actually says nothing about receiving the Eucharist unless I have missunderstood the term participation. Can. 1247 "On Sundays and other holy days of obligation, the faithful are obliged to participate in the Mass." Is the doctrine nowadays that it is very important (although not an obligation) to receive the Eucharist if you as a Catholic attend or hear Mass?