I still like doing both. Or actually all three, but not year-round.
(I haven’t done much of any of the three this winter, although I’m desperately trying to get back on track.)
To add on to the recommendation, while high-intensity intervals can be powerful sessions, too much can be counterproductive. Excess intensity can lead to injury or burnout. That may have happened with me and swimming last year. I ramped up the swim training last winter, and I did a lot of longer pull buoy sessions, something I never did before. I started to get noticeably stronger in the upper body. (I was suddenly able to do one-arm push-ups for the first time last spring, almost entirely because of the pull buoy workouts. Aside from the pulling sessions, I barely did any formal strength training at all — maybe one workout every 3 weeks — but I got better and better at push-ups without even practicing or training at push-ups.)
But I must have gotten sick of swimming subconsciously because one day in the late spring, I simply stopped swimming completely. No injury, no bad experience in a race (or any races at all). I just swam one day then never went back to the pool. I’ve only swam once in the last nine months.
I might get back to it again, sometime. If I start serious training for anything again, I will be careful not to overdo it. Not just because of injury concerns but also because of the possibility of burnout. That’s always a risk with too much high-intensity work. It doesn’t matter how fit you get in those workouts if they make you so sick of the sport that you quit it completely. The end result is less fitness, not more. I’m certainly a worse swimmer now than I was at this time last year. Nine months off will do that to you.
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