Picking three popular ASX blue chip shares is the easy part of this exercise.
The harder question is whether Commonwealth Bank of Australia (ASX: CBA), Macquarie Group Ltd (ASX: MQG), and CSL Ltd (ASX: CSL) can still justify their place in a portfolio two decades from now, not just today.
Each faces a genuine test over that horizon, and each currently looks like it can pass it, for different reasons.
Image source: Getty Images
Commonwealth Bank of Australia: the test is whether dominance survives disruption
CBA's 20-year test is not whether it remains Australia's largest bank. It has a good chance of it.
The real test is whether a dominant, capital-intensive incumbent can keep fending off digital disruption for two more decades, as it has for the past two.
In the first half of FY2026, CBA delivered a statutory net profit of $5.41 billion, up 5% on the prior corresponding period. Furthermore, CBA was able to continue ramping up technology spending to defend its lead.
However, at approximately 26 times forward earnings, CBA already prices in a significant amount of that continued dominance.
The bull case rests on scale, trust, and a banking app used by more Australians than any rivals. These advantages compound slowly but have proven durable across multiple banking cycles already.
Macquarie Group: the test is whether a trading culture can keep reinventing itself
Macquarie's 20-year test is different again.
Unlike a retail bank, Macquarie has already reinvented its business model multiple times across three decades, moving from a niche investment bank into one of the world's largest infrastructure and asset managers.
Morgans was impressed with Macquarie's FY2026 performance. The broker noted profit was up strongly on the prior year and ahead of consensus estimates. However, the broker flagged that, following recent share price strength, Macquarie shares are close to being fully valued today.
Yet for long-term holders, the case for Macquarie over two decades is less about today's price and more about betting on a management culture that has consistently found its next growth engine before the previous one matured. These intrinsic competitive advantages are harder to predict than a bank's mortgage book, but ones Macquarie has repeatedly delivered on.
CSL: the test is whether execution catches up to the moat
CSL's 20-year test is the most interesting of the three. This is because the moat is not in question, but the recent execution has been.
Morgans retains a buy rating on CSL with a price target of $147.59, arguing the issues behind the FY2026 guidance downgrade, including China albumin price pressure and US immunoglobulin channel inventory normalisation, are executional rather than structural.
CSL's barriers to entry in plasma collection and biotherapeutics remain extremely high, built over more than a century of operating history. That durability is why brokers have remained broadly constructive even amid a 60% decline from its all-time high.
CSL shares now trade on roughly 28 times earnings, expensive but insignificant over a 20-year time horizon.
The 20-year case for CSL is essentially a bet that an irreplaceable global franchise outlasts a difficult few years of execution. This is the kind of mis-pricing that long-term holders are supposed to be able to look through.
Why the 20-year framing changes the analysis for these ASX shares
Most "buy and hold" investors default to a five-year horizon. This is where current earnings momentum and broker price targets carry most of the weight.
Stretching that horizon to 20 years shifts the question from "what will this stock do next year" to "does the underlying moat survive technological, competitive, and cyclical change for two decades."
CBA's moat is threatened by digital disruption. Macquarie's moat depends on a culture of reinvention rather than a single fixed advantage. CSL's moat is arguably the strongest of the three on paper, but is currently being tested by execution rather than competition.
Foolish takeaway for these ASX shares
CBA, Macquarie, and CSL each represent a different kind of 20-year bet.
CBA is a bet that scale and trust keep beating disruption. Macquarie is a bet that a culture of reinvention will continue to work as well in 2046 as it has since the 1990s. CSL is a bet that an already-proven moat outlasts a rough few years of execution.
With strong track records on reinforcing their respective competitive advantages, these three blue-chip ASX shares are positioned to continue delivering well into the future.
