Tancock, 27, says that the fine margins in the sport and number of Britons who reached the finals of the various events mean there is plenty to celebrate.
"I don't know if swimming's funding will be cut - that is down to the powers that be," he told Eurosport. "We didn't get the medals we wanted or deserved, but you have to look at the bigger picture: Team GB did a fantastic job.
"The fans in the stands saw a British swimmer in almost every final: we were third in the table of countries that had the most swimmers in finals, behind America and Australia.
"We should be proud of what we've achieved, and hold our heads up high. We just need to convert the near-misses."
World champion Tancock finished fifth in the final of the 100m backstroke - won by American Matt Grevers in an Olympic record time - after placing sixth in the final in Beijing.
However his favoured distance, the 50m, is not an Olympic event: the Exeter swimmer retained his world title in that race in 2011 in Shanghai.
"The whole experience was amazing," he said. "I loved every minute of it, from being in the Olympic Village to standing behind the block before races with the roar from the crowd all around me.
"I'm not disappointed: I've given everything over the years. I was in the best possible shape and ready to go. I left no stone unturned.
"It's a cut-throat sport, where races are decided by a tenth of a second, or a hundredth of a second. It was an improvement on Beijing and the last World Championship [where he finished sixth in the 100].
"I would have loved to medal but you can throw a blanket over most finishes in the Olympics. It could have been a different result, but you've got to be positive.
"I'll be 31 in Rio, in my prime - I can't wait. I'd love to finish my career on a high there.
"I'd love to see the 50 become an Olympic event - the Brazilians love it, so it would be competitive! There are rumours every Olympics that it will be introduced, but it's never happened, so I won't be holding my breath."
Tancock has seen the positive effect that the Olympics can have upon young people, the potential future generations of athletes. He hopes that the sport will continue to receive backing from the authorities.
"Around the Olympics there has been a lot of talk about legacy: in the last few weeks, so many people have come up to me and told me they have been inspired to get in the pool," he revealed. "Stories about kids swimming widths without armbands for the first time - that is bigger than all of it.
"It's like when I was young - I was already in the pool, but when I saw snooker and tennis on TV it inspired me to get down the tennis court and snooker hall.
"Things that were set up 10 years ago are coming through now, and coaching is important in all this.
"I'm working with the Gillette 'Great Starts' campaign which inspires participation. It is separate from the funding issue, but the basic point remains: you need great coaches - to get people in there with grants - to do this.
"If you create great coaches, you create great athletes. Success breeds success.
"I've done my level 2 coaching, and if I can give a bit back when my career is over, that will be so important to me."
Gillette is offering to fund coaching qualifications for men across the UK as part of the ‘Great Starts’ campaign. To apply for a coaching grant visit Facebook.com/GilletteUK
- Sports & Recreation