Caps have followed the path of many electronic components in getting smaller along with increased performance. The physical size and lead diameter of pretty much everything is reduced. I have no problem at all with using this type of cap in older tube amps and they perform very well. The F&T cap leads are flimsy compared to the old Mallory caps in (say) silver face Fenders, now the Nichicons are thinner still.
Ripple current becomes an issue either when designing a PSU or when replacing capacitors so that the PSU ripple current doesn't exceed the capacitor rating. A cap operated beyond it's ripple rating will have increased temperature and shortened lifespan. Ripple current is related to ESR, so low-ESR caps have better ripple figures - important in high-demand applications such as switch-mode power supplies. Fitting a capacitor with a higher ripple current rating than necessary doesn't harm things - you get a slightly more efficient capacitor that runs cooler, though perhaps not noticeable. I liken this to using 5W resistors in a circuit where 2W would be fine.
There was a time where I never even looked at ripple and you'd have to dig out specs to find out what the value was for a certain cap. In my experience tube amps don't exhibit high enough demands on the power supply for ripple to be a real consideration. Having said that, If I'm shopping for caps at a given price I'll usually pick the ones that offer higher ripple figures - it can be a sign of better construction and durability and often a high ripple cap will have a better thermal rating, but not always.