How far do you swim each week? - 2022 update

Since this topic was last addressed 13 years ago and with the discovery of new nutrition breakthroughs, techniques, HIIT, core strengthening etc.  I'll ask.  How far do you swim each week?  Do you do the same thing?  I swim alone with a pair of Form goggles that I started using to recover from a stage 4 case of throat cancer (HPV P16 variant).  I had 6 rounds of chemo, 3 rounds of Cisplatin and 3 rounds of Carbosplatin (sp?).  The chemo roasted my primary right arm main vein so I'm hoping swimming and vascularity will improve my vein structure etc.

I was wondering what you guys do.  I'm knocking out 3-4000m, 3 times a week with my goggles, which I love.  I watch our masters team go no more than 3000m each practice and the schedule is all over the place which is why I chose the Form goggles.  I watch countless people jump in around me only to do the exact same workout, week after week, month after month and I hear them bemoan slow times and why no change or drop in their times.  I was wondering what fellow mid aged swimmers were doing weekly.  

Thanks.