Monero is highly popular to this date because its privacy for its user and for miner its cpu friendly but there is a catch Usually centralized exchange wont host Monero because its "privacy" usually it happen with centralized exchange that complies with the regulator.
Who said anything about Monero displacing Bitcoin as the top crypto in market cap? We're talking about Monero becoming an extremely-popular coin like it's the case with Ethereum and XRP these days. I don't see this happening anytime soon because of so much hatred against privacy coins. Especially by mainstream governments who don't want people getting financial privacy and freedom. If it can't be tracked or traced, then consider it an "Enemy of the State".
You can see why most exchanges have de-listed Monero from their platforms. Even some have gone as far as de-listing Litecoin after it added the "Mimblewimble" privacy technique. It's this reason why Monero will remain "under the radar" for as long as it lives. With ever-increasing regulations, it's likely Monero will end up being traded only on DEXs and P2P trading platforms. I think this is for the best. Who knows if this will strengthen Monero's decentralization in the long run? Just my thoughts